@article{calderon_funni_dickey_2022, title={Accuracy of Local Polarization Measurements by Scanning Transmission Electron Microscopy}, volume={28}, url={https://doi.org/10.1017/S1431927622012429}, DOI={10.1017/S1431927622012429}, abstractNote={Accurately determining local polarization at atomic resolution can unveil the mechanisms by which static and dynamical behaviors of the polarization occur, including domain wall motion, defect interaction, and switching mechanisms, advancing us toward the better control of polarized states in materials. In this work, we explore the potential of atomic-resolution scanning transmission electron microscopy to measure the projected local polarization at the unit cell length scale. ZnO and PbMg1/3Nb2/3O3 are selected as case studies, to identify microscope parameters that can significantly affect the accuracy of the measured projected polarization vector. Different STEM imaging modalities are used to determine the location of the atomic columns, which, when combined with the Born effective charges, allows for the calculation of local polarization. Our results indicate that differentiated differential phase contrast (dDPC) imaging enhances the accuracy of measuring local polarization relative to other imaging modalities, such as annular bright-field or integrated-DPC imaging. For instance, under certain experimental conditions, the projected spontaneous polarization for ZnO can be calculated with 1.4% error from the theoretical value. Furthermore, we quantify the influence of sample thickness, probe defocus, and crystal mis-tilt on the relative errors of the calculated polarization.}, number={6}, journal={Microscopy and Microanalysis}, author={Calderon, Sebastian and Funni, Stephen D and Dickey, Elizabeth C}, year={2022}, month={Dec}, pages={2047–2058} }
 @article{ryu_reddy_collazo_dickey_2022, title={Effects of temperature and oxygen partial pressure on electrical conductivity of Fe-doped β-Ga2O3 single crystals}, volume={120}, url={https://doi.org/10.1063/5.0093588}, DOI={10.1063/5.0093588}, abstractNote={In this work, we measure DC and AC conductivity and Hall voltage to determine the origin of electrical insulating properties of Fe-doped β-Ga2O3 single crystals, which are measured perpendicular to the 2¯01 crystallographic plane. We find that electrical conduction is predominantly controlled by free electrons in the temperature range 230–800 °C with the mutual compensation of the impurity donor (Si) and acceptor dopant (Fe), explaining the low concentration of free electrons and Fermi level pinning over a wide range of temperatures. Furthermore, the negative temperature-dependence of the carrier mobility indicates that it is limited by optical phonon scattering. Importantly, we find electrical conductivity to be largely independent of oxygen partial pressure (pO2) from air to 10−4 atm at 600 °C, but it becomes slightly dependent on pO2 at 800 °C, as intrinsic non-stoichiometric point defects begin to influence the charge balance.}, number={18}, journal={Applied Physics Letters}, author={Ryu, Gyunghyun and Reddy, Pramod and Collazo, Ramón and Dickey, Elizabeth C.}, year={2022}, month={May} }
 @article{fancher_burch_patala_dickey_2022, title={Implications of gnomonic distortion on electron backscatter diffraction and transmission Kikuchi diffraction}, volume={1}, ISSN={["1365-2818"]}, url={https://app.dimensions.ai/details/publication/pub.1143660520}, DOI={10.1111/jmi.13077}, abstractNote={The effect of gnomonic distortion on orientation indexing of electron backscatter diffraction patterns is explored through simulation of electron diffraction patterns for sample-to-detector geometries associated with transmission Kikuchi diffraction (TKD) and electron backscatter diffraction (EBSD). Simulated data were analysed by computing a similarity index for both Hough transformed data and simulated patterns to determine the sensitivity of each method for detecting subtle differences in the effect of gnomonic distortions on electron diffraction patterns. These results indicate that the increased gnomonic distortions in electron diffraction patterns for a TKD geometry enhance the sensitivity for detecting subtle differences in interband angles. Additionally, the utilisation of a Hough transform-based indexing approach further enhances the sensitivity.}, number={2}, journal={JOURNAL OF MICROSCOPY}, author={Fancher, Chris M. and Burch, Matthew J. and Patala, Srikanth and Dickey, Elizabeth C.}, year={2022}, month={Jan} }
 @article{zhao_funni_molina_dickey_jones_2022, title={Inhomogeneous electric field-induced structural changes in soft lead zirconate titanate ferroelectric ceramics}, volume={226}, ISSN={["1873-2453"]}, url={https://app.dimensions.ai/details/publication/pub.1144897101}, DOI={10.1016/j.actamat.2022.117682}, abstractNote={Under the application of an external voltage, high electric field concentrations can develop around the interdigitated electrode edges inside multilayer ceramic actuators (MLCAs). The spatial distribution of the local electrical field can create local inhomogeneity in the electromechanical response. To investigate the complex field inhomogeneity in MLCAs, partially electroded Nb-doped PbZrxTi1-xO3 samples were investigated via synchrotron-based high-energy X-ray diffraction (XRD) as a function of applied electric field. These in situ experiments allowed us to probe the structural changes as a function of position relative to the electrode edge and calculate the local degree of domain alignment, from which the local electric field directions were inferred. The domain switching behavior, both in amplitude and orientation, was found to be spatially dependent across the inactive regions in partially electroded samples. Specifically, the degree of domain alignment and field-induced phase transitions are amplified near the electrode edge. The orientation-dependent phase transitions are also amplified for the tetragonal composition near the morphotropic phase boundary (MPB), i.e., the Nb-doped PbZr0.53Ti0.47O3 composition. Finite element analysis (FEA) shows spatially-dependent, inhomogeneous electric field distributions in the partial-electrode samples, which closely match the experimentally inferred local electric field directions from XRD. The correlation of FEA and experimental data from XRD corroborates that the ferroelectric domain orientation distributions are being directed, primarily, in the direction of the electric field.}, number={ARTN 117682}, journal={ACTA MATERIALIA}, author={Zhao, Jianwei and Funni, Stephen D. and Molina, Emily R. and Dickey, Elizabeth C. and Jones, Jacob L.}, year={2022}, month={Mar} }
 @article{grimley_funni_green_dickey_2021, title={A thermal perspective of flash sintering: The effect of AC current ramp rate on microstructure evolution}, volume={41}, ISSN={["1873-619X"]}, url={https://doi.org/10.1016/j.jeurceramsoc.2020.11.040}, DOI={10.1016/j.jeurceramsoc.2020.11.040}, abstractNote={In flash sintering experiments, the thermal history of the sample is key to understanding the mechanisms underlying densification rate and final properties. By combining robust temperature measurements with current-ramp-rate control, this study examined the effects of the thermal profile on the flash sintering of yttria-stabilized zirconia, with experiments ranging from a few seconds to several hours. The final density was maximized at slower heating rates, although processes slower than a certain threshold led to grain growth. The amount of grain growth observed was comparable to a similar conventional thermal process. The bulk electrical conductivity correlated with the maximum temperature and cooling rate. The only property that exhibited behavior that could not be attributed to solely the thermal profile was the grain boundary conductivity, which was consistently higher than conventional in flash sintered samples. These results suggest that, during flash sintering, athermal electric field effects are relegated to the grain boundary.}, number={4}, journal={JOURNAL OF THE EUROPEAN CERAMIC SOCIETY}, publisher={Elsevier BV}, author={Grimley, Carolyn A. and Funni, Stephen and Green, Christopher and Dickey, Elizabeth C.}, year={2021}, month={Apr}, pages={2807–2817} }
 @article{miller_cabral_dickey_lebeau_reich_2021, title={Accounting for Location Measurement Error in Imaging Data With Application to Atomic Resolution Images of Crystalline Materials}, volume={64}, ISSN={["1537-2723"]}, url={https://app.dimensions.ai/details/publication/pub.1136536111}, DOI={10.1080/00401706.2021.1905070}, abstractNote={Scientists use imaging to identify objects of interest and infer properties of these objects. The locations of these objects are often measured with error, which when ignored leads to biased parameter estimates and inflated variance. Current measurement error methods require an estimate or knowledge of the measurement error variance to correct these estimates, which may not be available. Instead, we create a spatial Bayesian hierarchical model that treats the locations as parameters, using the image itself to incorporate positional uncertainty. We lower the computational burden by approximating the likelihood using a noncontiguous block design around the object locations. We use this model to quantify the relationship between the intensity and displacement of hundreds of atom columns in crystal structures directly imaged via scanning transmission electron microscopy (STEM). Atomic displacements are related to important phenomena such as piezoelectricity, a property useful for engineering applications like ultrasound. Quantifying the sign and magnitude of this relationship will help materials scientists more precisely design materials with improved piezoelectricity. A simulation study confirms our method corrects bias in the estimate of the parameter of interest and drastically improves coverage in high noise scenarios compared to non-measurement error models.}, number={1}, journal={TECHNOMETRICS}, author={Miller, Matthew J. and Cabral, Matthew J. and Dickey, Elizabeth C. and LeBeau, James M. and Reich, Brian J.}, year={2021}, month={Apr} }
 @article{kumar_baker_bowes_cabral_zhang_dickey_irving_lebeau_2021, title={Atomic-resolution electron microscopy of nanoscale local structure in lead-based relaxor ferroelectrics}, volume={20}, url={https://doi.org/10.1038/s41563-020-0794-5}, DOI={10.1038/s41563-020-0794-5}, abstractNote={Relaxor ferroelectrics, which can exhibit exceptional electromechanical coupling, are some of the most important functional materials, with applications ranging from ultrasound imaging to actuators. Since their discovery, their complex nanoscale chemical and structural heterogeneity has made the origins of their electromechanical properties extremely difficult to understand. Here, we employ aberration-corrected scanning transmission electron microscopy to quantify various types of nanoscale heterogeneities and their connection to local polarization in the prototypical relaxor ferroelectric system Pb(Mg1/3Nb2/3)O3–PbTiO3. We identify three main contributions that each depend on Ti content: chemical order, oxygen octahedral tilt and oxygen octahedral distortion. These heterogeneities are found to be spatially correlated with low-angle polar domain walls, indicating their role in disrupting long-range polarization and leading to nanoscale domain formation and the relaxor response. We further locate nanoscale regions of monoclinic-like distortion that correlate directly with Ti content and electromechanical performance. Through this approach, the connections between chemical heterogeneity, structural heterogeneity and local polarization are revealed, validating models that are needed to develop the next generation of relaxor ferroelectrics. Relaxor ferroelectric systems exhibit exceptional electromechanical coupling that arises from a variety of nanoscale chemical ordering. Here, scanning transmission electron microscopy is used to quantify this structural complexity directly.}, number={1}, journal={Nature Materials}, publisher={Springer Science and Business Media LLC}, author={Kumar, Abinash and Baker, Jonathon N. and Bowes, Preston C. and Cabral, Matthew J. and Zhang, Shujun and Dickey, Elizabeth C. and Irving, Douglas L. and LeBeau, James M.}, year={2021}, month={Jan}, pages={62–67} }
 @article{ryu_bowes_mcgarrahan_irving_dickey_2021, title={Fermi level pinning in Co-doped BaTiO3: Part I. DC and AC electrical conductivities and degradation behavior}, volume={105}, ISSN={["1551-2916"]}, url={https://doi.org/10.1111/jace.18042}, DOI={10.1111/jace.18042}, abstractNote={Abstract We explore the synergistic effects of co‐doping BaTiO 3 with a judicious combination of acceptors and donors to control the point defect chemistry and electrical properties, with the goal of simultaneously limiting the electronic and ionic conductivities over broad temperature and oxygen partial pressure ( p O 2 ) ranges. Specifically, we compare the temperature‐ and p O 2 ‐dependent electrical properties of BaTiO 3 ceramics acceptor‐doped with either Mn or Mg and co‐doped with a Y donor. This study, which is the first of a two‐part series, presents the electrical properties as a function of p O 2 , temperature, and time, focusing on the grain‐interior electrical response. The DC and AC electrical conductivity measurements reveal that co‐doping with Mn and Y can result in (1) increased electrical resistivity over a broad temperature range, (2) p O 2 ‐independent electrical conductivity in oxidizing conditions, and (3) improved time‐dependent dielectric degradation resistance. These behaviors are attributed to a Fermi level pinning effect, as is explained in the companion paper, which presents complementary density functional theory (DFT)‐based grand‐canonical defect chemistry models. The collective experimental and computational studies demonstrate that the p O 2 ‐independent electrical conductivity in the Mn and Y co‐doped BaTiO 3 is attributed to a Fermi level pinning mechanism arising from the multivalent Mn dopant, and the background reservoir of positive charge provided by the predominant substitution of Y on the Ba sites. The enhanced degradation resistance is attributed to a reduced oxygen vacancy concentration relative to the other doping chemistries.}, number={1}, journal={JOURNAL OF THE AMERICAN CERAMIC SOCIETY}, publisher={Wiley}, author={Ryu, Gyung Hyun and Bowes, Preston C. and McGarrahan, John R. and Irving, Douglas L. and Dickey, Elizabeth C.}, year={2021}, month={Jul} }
 @article{bowes_ryu_baker_dickey_irving_2021, title={Fermi level pinning in Co-doped BaTiO3: Part II. Defect chemistry models}, volume={7}, ISSN={["1551-2916"]}, url={https://doi.org/10.1111/jace.17938}, DOI={10.1111/jace.17938}, abstractNote={A first-principles informed grand canonical defect chemistry model capable of accounting for non-stoichiometry and partial equilibration of different sub-lattices is developed and used to study Mg and Mn doped, and (Mg+Y) and (Mn+Y) co-doped BaTiO3 to elucidate the role of Mn and Y in improving the resistivity and resistance degradation of BaTiO3 as observed by Ryu et al. in Part I of this series of papers. The model qualitatively captures the behavior of the samples in all conditions, reproducing the observed carrier plateau and increased resistivity of (Mn+Y) co-doped BaTiO3, and expected trends in the concentrations of free oxygen vacancies with doping. These trends reflect the observed differences in degradation characteristics, and help explain the substantially improved degradation resistance of the (Mn+Y) co-doped samples. Our model adds to the mechanism proposed by Yeoh et al. that the Fermi level is pinned by the multivalent character of MnTi in (Mn+Y) co-doped BaTiO3 by giving insight into the role of barium vacancies, the site preferences of the dopants, and defect complexes in this mechanism. These insights provide a set of criteria in the search for sets of co-dopants with similar behaviors.}, number={11}, journal={JOURNAL OF THE AMERICAN CERAMIC SOCIETY}, publisher={Wiley}, author={Bowes, Preston C. and Ryu, Gyung Hyun and Baker, Jonathon N. and Dickey, Elizabeth C. and Irving, Douglas L.}, year={2021}, month={Jul} }
 @article{zhao_funni_molina_dickey_jones_2021, title={Orientation-dependent, field-induced phase transitions in soft lead zirconate titanate piezoceramics}, volume={41}, ISSN={["1873-619X"]}, url={https://app.dimensions.ai/details/publication/pub.1134957541}, DOI={10.1016/j.jeurceramsoc.2021.01.043}, abstractNote={In situ high-energy X-ray diffraction (XRD) was performed on lead-zirconate-titanate-based ferroelectric materials with composition near the morphotropic phase boundary (MPB). The utilization of the two-dimensional area detector in in situ field-dependent experiments enables the complete analysis of the material response with respect to all azimuthal angles at each field amplitude. The studies reveal that the field-induced phase transition from tetragonal to rhombohedral is dependent on crystal orientation in Nb-doped PbZr0.53Ti0.47O3 that is in close compositional proximity to the MPB. However, only domain wall motion is activated in Nb-doped PbZr0.50Ti0.50O3, which is further in composition from the MPB. This synchrotron-based XRD characterization approach illustrates the importance in evaluating the orientation-dependence of phase transitions in piezoelectric and ferroelectric polycrystalline materials.}, number={6}, journal={JOURNAL OF THE EUROPEAN CERAMIC SOCIETY}, author={Zhao, Jianwei and Funni, Stephen D. and Molina, Emily R. and Dickey, Elizabeth C. and Jones, Jacob L.}, year={2021}, month={Jun}, pages={3357–3362} }
 @article{volk_kim_jamir_dickey_parsons_2021, title={Oxidative molecular layer deposition of PEDOT using volatile antimony(V) chloride oxidant}, volume={39}, ISSN={["1520-8559"]}, url={https://doi.org/10.1116/6.0000791}, DOI={10.1116/6.0000791}, abstractNote={Molecular layer deposition and chemical vapor deposition are emerging and promising techniques for the incorporation of high-performance conductive polymers into high surface area devices, such as sintered tantalum anodes for electrolytic capacitors. Until recently, vapor-phase synthesis of poly(3,4-ethylenedioxythiophene) (PEDOT) has relied on solid reactants which require relatively high temperatures and complex dosing schemes for sequential layer-by-layer processes. This work introduces a facile and high-performing layer-by-layer oxidative molecular layer deposition (oMLD) scheme using the volatile liquid oxidant antimony(V) chloride (SbCl5) to deposit PEDOT thin films. Effects of reactor parameters on PEDOT film characteristics are described, and the necessary foundation for future studies aiming to understand the nucleation and growth of layer-by-layer oMLD PEDOT is detailed.}, number={3}, journal={JOURNAL OF VACUUM SCIENCE & TECHNOLOGY A}, publisher={American Vacuum Society}, author={Volk, Amanda A. and Kim, Jung-Sik and Jamir, Jovenal and Dickey, Elizabeth C. and Parsons, Gregory N.}, year={2021}, month={May} }
 @article{funni_yang_cabral_ophus_chen_dickey_2021, title={Theory and application of the vector pair correlation function for real-space crystallographic analysis of order/disorder correlations from STEM images}, volume={9}, url={https://doi.org/10.1063/5.0058928}, DOI={10.1063/5.0058928}, abstractNote={Deviations of local structure and chemistry from the average crystalline unit cell are increasingly recognized to have a significant influence on the properties of many technologically important materials. Here, we present the vector pair correlation function (vPCF) as a new real-space crystallographic analysis method, which can be applied to atomic-resolution scanning transmission electron microscopy (STEM) images to quantify and analyze structural order/disorder correlations. Our STEM-based vPCFs have several advantages over radial PCFs and/or 3D pair distribution functions from x-ray total scattering: vPCFs explicitly retain crystallographic orientation information, are spatially resolved, can be applied directly on a sublattice basis, and are suitable for any material that can be imaged with STEM. To show the utility of our approach, we measure partial vPCFs in Ba 5 SmSn 3 Nb 7 O 30 (BSSN), a tetragonal tungsten bronze (TTB) structured complex oxide. Many TTBs are known to be classical or relaxor ferroelectrics, and these properties have been correlated with the presence of superlattice ordering. BSSN, specifically, exhibits relaxor behavior and an incommensurate structural modulation. From the vPCF data, we observe that, of the cation sites, only the Ba (A2) sublattice is structurally modulated. We then infer the local modulation vector and reveal a marked anisotropy in its correlation length. Finally, short-range correlated polar displacements on the B2 cation sites are observed. This work introduces the vPCF as a powerful real-space crystallography technique, which enables direct, robust quantification of short-to-long range order on a sublattice-specific basis and is applicable to a wide range of complex material types.}, number={9}, journal={APL Materials}, publisher={AIP Publishing}, author={Funni, Stephen D. and Yang, Zi Jin and Cabral, Matthew J. and Ophus, Colin and Chen, Xiang M. and Dickey, Elizabeth C.}, year={2021}, month={Sep}, pages={091110} }
 @inproceedings{kumar_baker_cabral_bowes_zhang_dickey_irving_lebeau_2020, title={Complementing X-ray & Neutron Diffuse Scatter Analysis with STEM to Understand Relaxor Behavior}, url={https://app.dimensions.ai/details/publication/pub.1129794183}, DOI={10.1017/S143192762001483X}, booktitle={Microscopy and Microanalysis}, author={Kumar, A and Baker, J and Cabral, M and Bowes, P and Zhang, S and Dickey, E and Irving, D and Lebeau, J}, year={2020}, month={Jan} }
 @article{ryu_lewis_kotsonis_maria_dickey_2020, title={Crystallization behavior of amorphous BaTiO3 thin films}, volume={55}, url={https://doi.org/10.1007/s10853-020-04637-z}, DOI={10.1007/s10853-020-04637-z}, number={21}, journal={Journal of Materials Science}, publisher={Springer Science and Business Media LLC}, author={Ryu, Gyung Hyun and Lewis, Neal P. and Kotsonis, George N. and Maria, Jon-Paul and Dickey, Elizabeth C.}, year={2020}, month={Jul}, pages={8793–8801} }
 @article{orera_wang_ferreiro-vila_serrano-zabaleta_larrañaga_laguna-bercero_dickey_rivadulla_muñoz_larrea_2020, title={Interfacial stability and ionic conductivity enhanced by dopant segregation in eutectic ceramics: the role of Gd segregation in doped CeO2/CoO and CeO2/NiO interfaces}, volume={8}, url={https://doi.org/10.1039/C9TA12315F}, DOI={10.1039/C9TA12315F}, abstractNote={Ionic charge balance at the interface of Gd-doped CeO<sub>2</sub>/CoO eutectic ceramics produces Gd segregation and increases the interfacial ionic conductivity.}, number={5}, journal={Journal of Materials Chemistry A}, publisher={Royal Society of Chemistry (RSC)}, author={Orera, Alodia and Wang, Funing and Ferreiro-Vila, Elías and Serrano-Zabaleta, Sonia and Larrañaga, Aitor and Laguna-Bercero, Miguel A. and Dickey, Elizabeth C. and Rivadulla, Francisco and Muñoz, M. Carmen and Larrea, Ángel}, year={2020}, pages={2591–2601} }
 @inproceedings{creange_cabral_funni_yang_zhu_chen_dickey_2020, title={Local Structure Quantification in Tetragonal Tungsten Bronze Structures Utilizing Convolutional Neural Networks}, url={https://app.dimensions.ai/details/publication/pub.1129794746}, DOI={10.1017/S1431927620020462}, abstractNote={An abstract is not available for this content so a preview has been provided. As you have access to this content, a full PDF is available via the ‘Save PDF’ action button.}, booktitle={Microscopy and Microanalysis}, author={Creange, N and Cabral, M and Funni, S and Yang, Z and Zhu, X and Chen, X and Dickey, E}, year={2020}, month={Jan} }
 @article{mukai_dickey_suh_2020, title={Low frequency dielectric properties related to structure of cotton fabrics}, volume={27}, ISSN={["1558-4135"]}, url={https://app.dimensions.ai/details/publication/pub.1124687757}, DOI={10.1109/TDEI.2019.008511}, abstractNote={The low-frequency dielectric properties of cotton fabrics in the fabric thickness direction are examined in relation to the fabric construction, thread count and solid volume fraction (SVF) at five different relative humidity levels. It is found that the real part of the relative permittivity increases with increase in thread count, and this is due to the associated increase in SVF. On the other hand, the imaginary part of the relative permittivity and loss tangent (dielectric loss) show no clear monotonic tendency to the SVF at highly moist environments. Permittivity is observed to change depending on fabric constructions under the controlled SVF. These observations indicate that, in addition to the SVF, the fabric geometrical parameters, which are influenced by construction methods, also need to be considered in low-frequency dielectric analysis.}, number={1}, journal={IEEE TRANSACTIONS ON DIELECTRICS AND ELECTRICAL INSULATION}, author={Mukai, Yusuke and Dickey, Elizabeth C. and Suh, Minyoung}, year={2020}, month={Feb}, pages={314–321} }
 @article{fahrenholtz_brennecka_dickey_ferreira_klein_mauro_ohji_riedel_viehland_wu_et al._2020, title={Remembering Joanna McKittrick}, volume={103}, url={https://doi.org/10.1111/jace.16967}, DOI={10.1111/jace.16967}, abstractNote={Journal of the American Ceramic SocietyVolume 103, Issue 4 p. 2277-2277 EDITORIAL Remembering Joanna McKittrick Bill Fahrenholtz, Corresponding Author Bill Fahrenholtz billf@mst.edu orcid.org/0000-0002-8497-0092 Journal of the American Ceramic Society Correspondence Bill Fahrenholtz, Journal of the American Ceramic Society. Email: billf@mst.eduSearch for more papers by this authorGeoff Brennecka, Geoff Brennecka orcid.org/0000-0002-4476-7655 Journal of the American Ceramic SocietySearch for more papers by this authorElizabeth Dickey, Elizabeth Dickey orcid.org/0000-0003-4005-7872 Journal of the American Ceramic SocietySearch for more papers by this authorJosé Ferreira, José Ferreira orcid.org/0000-0002-7520-2809 Journal of the American Ceramic SocietySearch for more papers by this authorLisa Klein, Lisa Klein Journal of the American Ceramic SocietySearch for more papers by this authorJohn Mauro, John Mauro orcid.org/0000-0002-4319-3530 Journal of the American Ceramic SocietySearch for more papers by this authorTatsuki Ohji, Tatsuki Ohji orcid.org/0000-0002-4880-9138 Journal of the American Ceramic SocietySearch for more papers by this authorRalf Riedel, Ralf Riedel orcid.org/0000-0001-6888-7208 Journal of the American Ceramic SocietySearch for more papers by this authorDwight Viehland, Dwight Viehland Journal of the American Ceramic SocietySearch for more papers by this authorYiquan Wu, Yiquan Wu orcid.org/0000-0002-1927-9748 Journal of the American Ceramic SocietySearch for more papers by this authorRong-Jun Xie, Rong-Jun Xie orcid.org/0000-0002-8387-1316 Journal of the American Ceramic SocietySearch for more papers by this authorYanchun Zhou, Yanchun Zhou orcid.org/0000-0002-4830-4287 Journal of the American Ceramic SocietySearch for more papers by this authorJonathon Foreman, Jonathon Foreman American Ceramic Society JournalsSearch for more papers by this authorMichelle Martin, Michelle Martin American Ceramic SocietySearch for more papers by this author Bill Fahrenholtz, Corresponding Author Bill Fahrenholtz billf@mst.edu orcid.org/0000-0002-8497-0092 Journal of the American Ceramic Society Correspondence Bill Fahrenholtz, Journal of the American Ceramic Society. Email: billf@mst.eduSearch for more papers by this authorGeoff Brennecka, Geoff Brennecka orcid.org/0000-0002-4476-7655 Journal of the American Ceramic SocietySearch for more papers by this authorElizabeth Dickey, Elizabeth Dickey orcid.org/0000-0003-4005-7872 Journal of the American Ceramic SocietySearch for more papers by this authorJosé Ferreira, José Ferreira orcid.org/0000-0002-7520-2809 Journal of the American Ceramic SocietySearch for more papers by this authorLisa Klein, Lisa Klein Journal of the American Ceramic SocietySearch for more papers by this authorJohn Mauro, John Mauro orcid.org/0000-0002-4319-3530 Journal of the American Ceramic SocietySearch for more papers by this authorTatsuki Ohji, Tatsuki Ohji orcid.org/0000-0002-4880-9138 Journal of the American Ceramic SocietySearch for more papers by this authorRalf Riedel, Ralf Riedel orcid.org/0000-0001-6888-7208 Journal of the American Ceramic SocietySearch for more papers by this authorDwight Viehland, Dwight Viehland Journal of the American Ceramic SocietySearch for more papers by this authorYiquan Wu, Yiquan Wu orcid.org/0000-0002-1927-9748 Journal of the American Ceramic SocietySearch for more papers by this authorRong-Jun Xie, Rong-Jun Xie orcid.org/0000-0002-8387-1316 Journal of the American Ceramic SocietySearch for more papers by this authorYanchun Zhou, Yanchun Zhou orcid.org/0000-0002-4830-4287 Journal of the American Ceramic SocietySearch for more papers by this authorJonathon Foreman, Jonathon Foreman American Ceramic Society JournalsSearch for more papers by this authorMichelle Martin, Michelle Martin American Ceramic SocietySearch for more papers by this author First published: 30 December 2019 https://doi.org/10.1111/jace.16967Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume103, Issue4April 2020Pages 2277-2277 RelatedInformation}, number={4}, journal={Journal of the American Ceramic Society}, publisher={Wiley}, author={Fahrenholtz, Bill and Brennecka, Geoff and Dickey, Elizabeth and Ferreira, José and Klein, Lisa and Mauro, John and Ohji, Tatsuki and Riedel, Ralf and Viehland, Dwight and Wu, Yiquan and et al.}, year={2020}, month={Apr}, pages={2277–2277} }
 @article{long_klein_dickey_2019, title={Barrier formation at BaTiO3 interfaces with Ni and NiO}, volume={466}, ISSN={0169-4332}, url={http://dx.doi.org/10.1016/j.apsusc.2018.10.040}, DOI={10.1016/j.apsusc.2018.10.040}, abstractNote={Barium Titanate and Ni-based multilayer ceramic capacitors have wide commercial applicability, and interfaces are critical to the overall device behavior as they can help control unwanted leakage currents. Here we make use of photoemission methods to investigate the electrostatic barriers formed at BaTiO3/Ni(O) interfaces to understand the implications for electron injection. We find the interface Fermi level in BaTiO3 to evolve smoothly during Ni deposition with a Schottky barrier height for electrons of 0.68 eV, whereas with NiO the Fermi level evolves rapidly with an electron injection barrier of 1.49 eV. In-situ poling shows the Schottky barrier at the BaTiO3/Ni interface is not significantly altered by ferroelectric polarization, consistent with the good screening of the Ni electrode. This study presents a direct quantitative measurement of the interface barrier heights and highlights the significance of the oxidation state of the electrode.}, journal={Applied Surface Science}, publisher={Elsevier BV}, author={Long, Daniel M. and Klein, Andreas and Dickey, Elizabeth C.}, year={2019}, month={Feb}, pages={472–476} }
 @article{kang_floyd_lowum_long_dickey_maria_2019, title={Cold sintering with dimethyl sulfoxide solutions for metal oxides}, volume={54}, ISSN={0022-2461 1573-4803}, url={http://dx.doi.org/10.1007/s10853-019-03410-1}, DOI={10.1007/s10853-019-03410-1}, number={10}, journal={Journal of Materials Science}, publisher={Springer Science and Business Media LLC}, author={Kang, Xiaoyu and Floyd, Richard and Lowum, Sarah and Long, Daniel and Dickey, Elizabeth and Maria, Jon-Paul}, year={2019}, month={Feb}, pages={7438–7446} }
 @article{de guire_bartolo_brindle_devanathan_dickey_fessler_french_fotheringham_harmer_lara‐curzio_et al._2019, title={Data‐driven glass/ceramic science research: Insights from the glass and ceramic and data science/informatics communities}, volume={102}, ISSN={0002-7820 1551-2916}, url={http://dx.doi.org/10.1111/jace.16677}, DOI={10.1111/jace.16677}, abstractNote={Abstract Data‐driven science and technology have helped achieve meaningful technological advancements in areas such as materials/drug discovery and health care, but efforts to apply high‐end data science algorithms to the areas of glass and ceramics are still limited. Many glass and ceramic researchers are interested in enhancing their work by using more data and data analytics to develop better functional materials more efficiently. Simultaneously, the data science community is looking for a way to access materials data resources to test and validate their advanced computational learning algorithms. To address this issue, The American Ceramic Society (ACerS) convened a Glass and Ceramic Data Science Workshop in February 2018, sponsored by the National Institute for Standards and Technology (NIST) Advanced Manufacturing Technologies (AMTech) program. The workshop brought together a select group of leaders in the data science, informatics, and glass and ceramics communities, ACerS, and Nexight Group to identify the greatest opportunities and mechanisms for facilitating increased collaboration and coordination between these communities. This article summarizes workshop discussions about the current challenges that limit interactions and collaboration between the glass and ceramic and data science communities, opportunities for a coordinated approach that leverages existing knowledge in both communities, and a clear path toward the enhanced use of data science technologies for functional glass and ceramic research and development.}, number={11}, journal={Journal of the American Ceramic Society}, publisher={Wiley}, author={De Guire, Eileen and Bartolo, Laura and Brindle, Ross and Devanathan, Ram and Dickey, Elizabeth C. and Fessler, Justin and French, Roger H. and Fotheringham, Ulrich and Harmer, Martin and Lara‐Curzio, Edgar and et al.}, year={2019}, month={Jul}, pages={6385–6406} }
 @article{grimley_prette_dickey_2019, title={Effect of boundary conditions on reduction during early stage flash sintering of YSZ}, volume={174}, ISSN={1359-6454}, url={http://dx.doi.org/10.1016/j.actamat.2019.05.001}, DOI={10.1016/j.actamat.2019.05.001}, abstractNote={The onset of flash sintering is generally considered to be predominantly a function of the conductivity of a given ceramic, the furnace temperature, and the electric field. However, the evolution of the point defect profiles in ionic conductors such as yttria-stabilized zirconia (YSZ) can complicate the picture of homogeneous Joule heating and thermal runaway during DC flash sintering. Here, 8 mol% YSZ pellets were partially flash sintered under a DC bias using various current densities and hold times. The electrode geometry was varied to modulate the oxygen ion flux available to the cathode to compare the effects on the resulting oxygen vacancy inhomogeneity. The contribution from fundamental and experimental factors to the cathodic reduction reaction is also discussed, such as interface reaction kinetics and sample geometry. Local reduction of the ceramic was inevitably observed under all current densities and the resulting microstructural inhomogeneity was explained as the result of a transient conductivity asymmetry. This asymmetry was the result of the enhanced electronic conductivity in the cathode region to a value significantly greater than the ionic conductivity of near-stoichiometric YSZ. The link between the local conductivity, voltage and Joule heating is mathematically demonstrated to result in an asymmetric heating profile.}, journal={Acta Materialia}, publisher={Elsevier BV}, author={Grimley, Carolyn A. and Prette, Andre L.G. and Dickey, Elizabeth C.}, year={2019}, month={Aug}, pages={271–278} }
 @article{long_creange_moballegh_dickey_2019, title={Electromigration-induced leakage current enhancement and its anisotropy in single crystal TiO 2}, volume={125}, ISSN={0021-8979 1089-7550}, url={http://dx.doi.org/10.1063/1.5090402}, DOI={10.1063/1.5090402}, abstractNote={Time-dependent increases in electrical conductivity in dielectrics exposed to a direct-current voltage bias can be detrimental to device reliability and lifetime, while the same phenomenon may be exploited for resistive switching functionality. The applied electric field induces the electromigration of charged point defects, resulting in spatially inhomogeneous stoichiometry and modifications in the electrode electrostatics. Herein, we monitor the time-dependent changes in leakage current in rutile TiO2 with platinum electrodes. Current–voltage measurements before and after the extended electrical biasing demonstrate that changes in the electrostatics of the cathode Schottky barrier are responsible for the time-dependent increases in leakage current. We also find that electromigration is accelerated along the ⟨001⟩ relative to the ⟨010⟩ crystallographic direction in contrast to what would be predicted by high-temperature diffusion kinetics. We find the observed anisotropic behavior to be consistent with a change in the defect charge state of the titanium interstitials and dominant transport path at lower temperatures. A comparison of optical color front migration kinetics to the temporal evolution of leakage current further supports the interpretation that ionic electromigration near the cathode interface is responsible for the increased leakage current in the electrically degraded state.}, number={18}, journal={Journal of Applied Physics}, publisher={AIP Publishing}, author={Long, Daniel and Creange, Nicole and Moballegh, Ali and Dickey, Elizabeth C.}, year={2019}, month={May}, pages={184101} }
 @article{li_cabral_xu_cheng_dickey_lebeau_wang_luo_taylor_hackenberger_et al._2019, title={Giant piezoelectricity of Sm-doped Pb(Mg1/3Nb2/3)O-3-PbTiO3 single crystals}, volume={364}, ISSN={["1095-9203"]}, url={https://doi.org/10.1126/science.aaw2781}, DOI={10.1126/science.aaw2781}, abstractNote={High-performance piezoelectrics benefit transducers and sensors in a variety of electromechanical applications. The materials with the highest piezoelectric charge coefficients (d33) are relaxor-PbTiO3 crystals, which were discovered two decades ago. We successfully grew Sm-doped Pb(Mg1/3Nb2/3)O3-PbTiO3 (Sm-PMN-PT) single crystals with even higher d33 values ranging from 3400 to 4100 picocoulombs per newton, with variation below 20% over the as-grown crystal boule, exhibiting good property uniformity. We characterized the Sm-PMN-PT on the atomic scale with scanning transmission electron microscopy and made first-principles calculations to determine that the giant piezoelectric properties arise from the enhanced local structural heterogeneity introduced by Sm3+ dopants. Rare-earth doping is thus identified as a general strategy for introducing local structural heterogeneity in order to enhance the piezoelectricity of relaxor ferroelectric crystals.}, number={6437}, journal={SCIENCE}, publisher={American Association for the Advancement of Science (AAAS)}, author={Li, Fei and Cabral, Matthew J. and Xu, Bin and Cheng, Zhenxiang and Dickey, Elizabeth C. and LeBeau, James M. and Wang, Jianli and Luo, Jun and Taylor, Samuel and Hackenberger, Wesley and et al.}, year={2019}, month={Apr}, pages={264-+} }
 @article{kang_floyd_lowum_cabral_dickey_maria_2019, title={Mechanism studies of hydrothermal cold sintering of zinc oxide at near room temperature}, volume={102}, ISSN={0002-7820 1551-2916}, url={http://dx.doi.org/10.1111/JACE.16340}, DOI={10.1111/jace.16340}, abstractNote={Zinc oxide densification mechanisms occurring during the cold sintering process (CSP) are examined by investigating specifically the effects of ion concentration in solution, temperature, pressure, and die sealing. The experiments suggest that mass transport through solution is a primary densification mechanism and that either a pre-loaded solution or grain dissolution can supply migrating ions. Additionally, results indicate cold sintering zinc oxide requires a critical pressure value, above which densification is relatively pressure independent under the majority of process conditions. This critical pressure is related to thermal expansion of the liquid and determines the uniaxial pressure threshold for densification. The data supports a three-stage interpretation of cold sintering, which includes quick compaction, grain rearrangement, and dissolution-reprecipitation events. Further, it is observed that under the lowest temperature conditions a net decrease in particle size can occur during the cold sintering process.}, number={8}, journal={Journal of the American Ceramic Society}, publisher={Wiley}, author={Kang, Xiaoyu and Floyd, Richard and Lowum, Sarah and Cabral, Matthew and Dickey, Elizabeth and Maria, Jon‐Paul}, year={2019}, month={Feb}, pages={4459–4469} }
 @inproceedings{wright_brent_dickey_weems_reich_jackson_2019, title={North Carolina central and North Carolina state universities bridge-to-Ph.D. Program for master's underrepresented minority students}, booktitle={CoNECD 2019 - Collaborative Network for Engineering and Computing Diversity}, author={Wright, AR and Brent, R and Dickey, EC and Weems, K and Reich, B and Jackson, CR}, year={2019}, month={Apr} }
 @article{de souza_dickey_2019, title={The effect of space-charge formation on the grain-boundary energy of an ionic solid}, volume={377}, ISSN={1364-503X 1471-2962}, url={http://dx.doi.org/10.1098/rsta.2018.0430}, DOI={10.1098/rsta.2018.0430}, abstractNote={Taking the model system of an oxide containing acceptor dopant cations and charge-compensating oxygen vacancies, we calculate at the continuum level the change in the excess grain-boundary energy of an ionic solid upon space-charge formation. Two different cases are considered for the space-charge layers: (i) only vacancies attain electrochemical equilibrium and (ii) both dopants and vacancies attain electrochemical equilibrium. The changes calculated for a specific set of grain boundaries indicate that, depending on dopant concentration, space-charge formation can decrease the excess free energy by up to 15% in the first case and by up to 45% in the second case. The possibility of the excess grain-boundary energy going to zero and the possible effects of an external electric field on the excess grain-boundary energy are also discussed. This article is part of a discussion meeting issue 'Energy materials for a low carbon future'.}, number={2152}, journal={Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences}, publisher={The Royal Society}, author={De Souza, R. A. and Dickey, E. C.}, year={2019}, month={Jul}, pages={20180430} }
 @article{lebeau_dickey_augustyn_hesterberg_brown_2018, title={Acquisition of a microscope for in situ studies of hard and soft matter}, volume={24}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S143192761801214X}, DOI={10.1017/S143192761801214X}, number={S1}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={LeBeau, James M. and Dickey, Elizabeth C. and Augustyn, Veronica and Hesterberg, Dean L. and Brown, Ashley C.}, year={2018}, month={Aug}, pages={2332–2333} }
 @article{long_cai_baker_bowes_bayer_wang_wang_chen_randall_irving_et al._2018, title={Conductivity of iron‐doped strontium titanate in the quenched and degraded states}, volume={102}, ISSN={0002-7820 1551-2916}, url={http://dx.doi.org/10.1111/jace.16212}, DOI={10.1111/jace.16212}, abstractNote={The electrical behavior of iron-doped strontium titanate (Fe:SrTiO3) single crystals equilibrated at 900°C and quenched below 400°C at various oxygen partial pressures () was investigated via impedance spectroscopy and compared to defect chemistry models. Fe:SrTiO3 annealed and quenched between 1.2 × 10−14 and 2.0 × 10−4 Pa exhibits a conduction activation energy (EA) around 0.6 eV, consistent with ionic conduction of oxygen vacancies. However, sudden changes in EA are found to either side of this range; a transition from 0.6 to 1 eV is found in more oxidizing conditions, while a sudden transition to 1.1 and then 0.23 eV is found in reducing These transitions, not described by the widely used canonical model, are consistent with predictions of transitions from ionic to electronic conductivity, based on first principles point defect chemistry simulations. These models demonstrate that activation energies in mixed conductors may not correlate to specific conduction mechanisms, but are determined by the cumulative response of all operative conduction processes and are very sensitive to impurities. A comparison to electrically degraded Fe:SrTiO3 provides insight into the origins of the conductivity activation energies observed in those samples.}, number={6}, journal={Journal of the American Ceramic Society}, publisher={Wiley}, author={Long, Daniel M. and Cai, Biya and Baker, Jonathon N. and Bowes, Preston C. and Bayer, Thorsten J.M. and Wang, Jian‐Jun and Wang, Rui and Chen, Long‐Qing and Randall, Clive A. and Irving, Douglas L. and et al.}, year={2018}, month={Dec}, pages={3567–3577} }
 @article{king_el-hinnawy_borodulin_ezis_luu_salmon_gu_nichols_dickey_maria_et al._2018, title={Connecting post-pulsing electrical and microstructural features in GeTe-based inline phase change switches}, volume={124}, ISSN={0021-8979 1089-7550}, url={http://dx.doi.org/10.1063/1.5031840}, DOI={10.1063/1.5031840}, abstractNote={Plan view scanning transmission electron microscopy was used to investigate the microstructural connections to device resistance in inline phase change switch devices. It was revealed that massive structural changes occur in GeTe during switching, most notably the formation of an assembly of voids along the device centerline and large GeTe grains on either side of an “active region.” Restructuring of this variety was tied to changes in ON-state resistance with increasing pulse number, where initially porous and fine-grained (10-20 nm) GeTe was converted to large crystalline domains comprising the majority of the RF gap (400-700 nm). A phenomenological model for this microstructure is presented in which the OFF pulse melts a given width of GeTe, and upon cooling crystalline material outside the melt region acts as a template for an inward-propagating crystalline growth front. The voids observed along the device centerline were correlated to increasing OFF state resistance and a relatively stable ON state with increasing pulse number via a series resistance model. As a result of this analysis, OFF state resistance was suggested as an early indicator of device reliability. An improved GeTe deposition process was implemented to limit void formation, which is shown to have a more stable OFF-state resistance with increasing pulse number.}, number={19}, journal={Journal of Applied Physics}, publisher={AIP Publishing}, author={King, Matthew R. and El-Hinnawy, Nabil and Borodulin, Pavel and Ezis, Andy and Luu, Vivien and Salmon, Mike and Gu, Jitty and Nichols, Doyle T. and Dickey, Elizabeth and Maria, Jon-Paul and et al.}, year={2018}, month={Nov}, pages={195103} }
 @article{cabral_zhang_dickey_lebeau_2018, title={Gradient chemical order in the relaxor Pb(Mg1∕3Nb2∕3)O3}, volume={112}, ISSN={0003-6951 1077-3118}, url={http://dx.doi.org/10.1063/1.5016561}, DOI={10.1063/1.5016561}, abstractNote={Here, we apply aberration-corrected scanning transmission electron microscopy to quantify chemical ordering in the relaxor Pb(Mg1∕3Nb2∕3)O3 (PMN). We find that contrary to the prevailing model of a binary distribution of chemically ordered regions within a disordered matrix, the degree of ordering smoothly varies within an ordered domain and approaches a minimum at anti-phase boundaries. These results provide direct insight into the nature of cation ordering in this important prototypical relaxor material.}, number={8}, journal={Applied Physics Letters}, publisher={AIP Publishing}, author={Cabral, Matthew J. and Zhang, Shujun and Dickey, Elizabeth C. and LeBeau, James M.}, year={2018}, month={Feb}, pages={082901} }
 @article{cabral_dickey_lebeau_2018, title={Quantification of Structural Correlation in STEM Images using the Projected Pair Distribution Function}, volume={24}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927618000788}, DOI={10.1017/S1431927618000788}, number={S1}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Cabral, Matthew J. and Dickey, Elizabeth C. and LeBeau, James M.}, year={2018}, month={Aug}, pages={58–59} }
 @article{dickey_arthur_2017, title={Big data meets materials science: Training the future generation}, volume={96}, number={6}, journal={American Ceramic Society Bulletin}, author={Dickey, E and Arthur, G}, year={2017}, pages={40–44} }
 @article{maria_kang_floyd_dickey_guo_guo_baker_funihashi_randall_2017, title={Cold sintering: Current status and prospects}, volume={32}, ISSN={0884-2914 2044-5326}, url={http://dx.doi.org/10.1557/jmr.2017.262}, DOI={10.1557/jmr.2017.262}, number={17}, journal={Journal of Materials Research}, publisher={Cambridge University Press (CUP)}, author={Maria, Jon-Paul and Kang, Xiaoyu and Floyd, Richard D. and Dickey, Elizabeth C. and Guo, Hanzheng and Guo, Jing and Baker, Amanda and Funihashi, Shuichi and Randall, Clive A.}, year={2017}, month={Jul}, pages={3205–3218} }
 @article{cabral_zhang_chi_reich_dickey_lebeau_2017, title={Correlating Local Chemistry and Local Cation Displacements in the Relaxor Ferroelectric PMN}, volume={23}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927617008741}, DOI={10.1017/S1431927617008741}, number={S1}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Cabral, Matthew J. and Zhang, Shujun and Chi, Jocelyn and Reich, Brian J. and Dickey, Elizabeth C. and LeBeau, James M.}, year={2017}, month={Jul}, pages={1616–1617} }
 @article{baker_bowes_long_moballegh_harris_dickey_irving_2017, title={Defect mechanisms of coloration in Fe-doped SrTiO3 from first principles}, volume={110}, ISSN={0003-6951 1077-3118}, url={http://dx.doi.org/10.1063/1.4978861}, DOI={10.1063/1.4978861}, abstractNote={To understand the underlying defect mechanisms governing the coloration of Fe-doped SrTiO3 (Fe:STO), density functional theory calculations were used to determine defect formation energies and to interpret optical absorption spectra. A grand canonical defect equilibrium model was developed using the calculated formation energies, which enabled connection to annealing experiments. It was found that FeTi0 is stable in oxidizing conditions and leads to the optical absorption signatures in oxidized Fe:STO, consistent with experiment. Fe:STO was found to transition from brown to transparent as PO2 was reduced during annealing. The defect equilibrium model reproduces a consistent PO2 of this coloration transition. Most critical to reproducing the PO2 of the coloration transition was inclusion of a FeTi-VO first nearest neighbor complex, which was found to be strongly interacting. The coloration transition PO2 was found to be insensitive to the presence of minority background impurities, slightly sensitive to Fe content, and more sensitive to annealing temperature.}, number={12}, journal={Applied Physics Letters}, publisher={AIP Publishing}, author={Baker, Jonathon N. and Bowes, Preston C. and Long, Daniel M. and Moballegh, Ali and Harris, Joshua S. and Dickey, Elizabeth C. and Irving, Douglas L.}, year={2017}, month={Mar}, pages={122903} }
 @article{dickey_pawlak_berger_merino_sayir_2017, title={Guest Editors' Preface}, volume={52}, ISSN={["1573-4803"]}, url={https://app.dimensions.ai/details/publication/pub.1083753679}, DOI={10.1007/s10853-017-0843-x}, number={10}, journal={JOURNAL OF MATERIALS SCIENCE}, publisher={Springer Nature}, author={Dickey, Elizabeth C. and Pawlak, Dorota A. and Berger, Marie-Helene and Merino, Rosa I. and Sayir, Ali}, year={2017}, month={May}, pages={5475–5476} }
 @article{donovan_long_moballegh_creange_dickey_hopkins_2017, title={Impact of intrinsic point defect concentration on thermal transport in titanium dioxide}, volume={127}, ISSN={1359-6454}, url={http://dx.doi.org/10.1016/j.actamat.2017.01.018}, DOI={10.1016/j.actamat.2017.01.018}, abstractNote={The thermal conductivity of functional oxide materials can be significantly impacted by variations in point defect concentration, especially at high concentrations where defect interactions can result in extended defects and secondary phase formation. In this work, we systematically study the impact of high point defect concentrations on thermal transport in rutile TiO2. Using atmospherically controlled annealing, we vary equilibrium point defect concentrations and measure the resulting thermal conductivity using time domain thermoreflectance. We verify our results with analytical modeling and find that it is not until very high defect concentrations (> 0.5 mol.%) that the phonon thermal conductivity is impacted. We vary the partial pressure of oxygen to low enough levels that sub-stoichiometric Magnéli phases form and find that these highly defective phases severely reduce the thermal conductivity and anisotropy from intrinsic levels.}, journal={Acta Materialia}, publisher={Elsevier BV}, author={Donovan, Brian F. and Long, Daniel M. and Moballegh, Ali and Creange, Nicole and Dickey, Elizabeth C. and Hopkins, Patrick E.}, year={2017}, month={Apr}, pages={491–497} }
 @article{chen_dickey_2017, title={Indentation-induced deformation mechanisms in laser-processed directionally solidified WC–W2C eutectoids}, volume={52}, ISSN={0022-2461 1573-4803}, url={http://dx.doi.org/10.1007/s10853-017-0757-7}, DOI={10.1007/s10853-017-0757-7}, number={10}, journal={Journal of Materials Science}, publisher={Springer Nature}, author={Chen, Wei-Ting and Dickey, Elizabeth C.}, year={2017}, month={Jan}, pages={5511–5519} }
 @article{burch_fancher_patala_de graef_dickey_2017, title={Mapping 180° polar domains using electron backscatter diffraction and dynamical scattering simulations}, volume={173}, ISSN={0304-3991}, url={http://dx.doi.org/10.1016/j.ultramic.2016.11.013}, DOI={10.1016/j.ultramic.2016.11.013}, abstractNote={A novel technique, which directly and nondestructively maps polar domains using electron backscatter diffraction (EBSD) is described and demonstrated. Through dynamical diffraction simulations and quantitative comparison to experimental EBSD patterns, the absolute orientation of a non-centrosymmetric crystal can be determined. With this information, the polar domains of a material can be mapped. The technique is demonstrated by mapping the non-ferroelastic, or 180°, ferroelectric domains in periodically poled LiNbO3 single crystals. Further, the authors demonstrate the possibility of mapping polarity using this technique in other polar materials system.}, journal={Ultramicroscopy}, publisher={Elsevier BV}, author={Burch, Matthew J. and Fancher, Chris M. and Patala, Srikanth and De Graef, Marc and Dickey, Elizabeth C.}, year={2017}, month={Feb}, pages={47–51} }
 @article{lebeau_cabral_dycus_grimley_zhang_dickey_2017, title={Quantifying Local Structure of Complex Oxides Using Accurate and Precise Scanning Transmission Electron Microscopy}, volume={23}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927617008856}, DOI={10.1017/S1431927617008856}, number={S1}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={LeBeau, James M. and Cabral, Matthew and Dycus, J. Houston and Grimley, Everett and Zhang, Shujun and Dickey, Elizabeth}, year={2017}, month={Jul}, pages={1638–1639} }
 @article{chen_dickey_2016, title={Crystallographic orientation relationships and interfaces in laser-processed directionally solidified WC–W2C eutectoid ceramics}, volume={51}, ISSN={0022-2461 1573-4803}, url={http://dx.doi.org/10.1007/s10853-016-9749-2}, DOI={10.1007/s10853-016-9749-2}, number={9}, journal={Journal of Materials Science}, publisher={Springer Science and Business Media LLC}, author={Chen, Wei-Ting and Dickey, Elizabeth C.}, year={2016}, month={Jan}, pages={4371–4378} }
 @article{wang_huang_bayer_moballegh_cao_klein_dickey_irving_randall_chen_et al._2016, title={Defect chemistry and resistance degradation in Fe-doped SrTiO3 single crystal}, volume={108}, ISSN={1359-6454}, url={http://dx.doi.org/10.1016/j.actamat.2016.02.022}, DOI={10.1016/j.actamat.2016.02.022}, abstractNote={Defect chemistry and transport in Fe-doped SrTiO3 single crystal are studied to understand its resistance degradation mechanism. The temporal evolution of electric conductivity under a voltage stress was obtained computationally by solving the transport equations for ionic and electronic defects coupled with the defect reaction equilibrium equations. The computational results are compared to the corresponding experimental measurement under similar conditions. It is shown that the local electron and hole concentrations are controlled by the local electronic defect equilibria rather than by their quasi-steady state diffusional transport. It is the electric field-induced migration of oxygen vacancies and the subsequent instantaneous reestablishment of the local defect equilibria that lead to the resistance degradation. The resistance degradation behavior and the defect distributions under a long-term voltage stress are strongly influenced by the sample-annealing oxygen partial pressure, degrading electric field, and temperature. The present study contributes to the understanding of resistance degradation mechanism and provides guidance to improve the lifetime and reliability of wide band-gap semiconducting capacitors.}, journal={Acta Materialia}, publisher={Elsevier BV}, author={Wang, Jian-Jun and Huang, Hou-Bing and Bayer, Thorsten J. M. and Moballegh, Ali and Cao, Ye and Klein, Andreas and Dickey, Elizabeth C. and Irving, Douglas L. and Randall, Clive A. and Chen, Long-Qing and et al.}, year={2016}, month={Apr}, pages={229–240} }
 @article{cabral_zhang_dickey_lebeau_2016, title={Direct observation of local chemistry and local cation displacements in the relaxor ferroelectric PMN-PT}, volume={22}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/s1431927616007856}, DOI={10.1017/s1431927616007856}, number={S3}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Cabral, Matthew J. and Zhang, Shujun and Dickey, Elizabeth C. and LeBeau, James M.}, year={2016}, month={Jul}, pages={1402–1403} }
 @article{chen_white_goto_dickey_2016, title={Directionally Solidified Boride and Carbide Eutectic Ceramics}, volume={99}, ISSN={0002-7820}, url={http://dx.doi.org/10.1111/jace.14287}, DOI={10.1111/jace.14287}, abstractNote={Borides and carbides generally have outstanding hardness, excellent wear resistance, and high melting points due to their covalent bonding. Directionally solidified eutectic (DSE) composites of boride and carbide constituent phases have been investigated since the 1970s as an approach to produce dense composite microstructures with added control over the microstructure. A variety of DSE ceramic composites have been developed and evaluated as potential materials for structural and functional applications due to their unique thermo-electro-mechanical properties. Renewed interest over the past few decades has been motivated, in part, by the needs for ultrahigh-temperature composites for aerospace applications along with low-density composites for armor applications. Some directionally solidified boride and carbide DSEs exhibit advantages in material properties over monolithic materials. This study reviews historical and recent research on processing methods, microstructure, crystallography, and material properties (mechanical, electrical, thermal properties, and oxidation resistance) of directionally solidified boride and carbide eutectic ceramic composites. Opportunities along with current limitations and needs for future developments are also reviewed and discussed.}, number={6}, journal={Journal of the American Ceramic Society}, publisher={Wiley}, author={Chen, Wei-Ting and White, Ryan M. and Goto, Takashi and Dickey, Elizabeth C.}, editor={Green, D. J.Editor}, year={2016}, month={May}, pages={1837–1851} }
 @article{nowotny_bak_dickey_sigmund_alim_2016, title={Electrical Conductivity, Thermoelectric Power, and Equilibration Kinetics of Nb-Doped TiO2}, volume={120}, ISSN={1089-5639 1520-5215}, url={http://dx.doi.org/10.1021/acs.jpca.6b04104}, DOI={10.1021/acs.jpca.6b04104}, abstractNote={This work considers the equilibration kinetics of Nb-doped TiO2 single crystal (0.066 atom % Nb) during oxidation and reduction within a wide range of temperature (1073-1298 K) and oxygen activity (10(-14)-10(5) Pa). The associated semiconducting properties were determined using simultaneous measurements of both electrical conductivity and thermoelectric power. It is shown that the chemical diffusion coefficient in the strongly reducing regime, p(O2) < 10(-5) Pa, is 4 orders of magnitude larger than that in the reducing and oxidizing regimes, 10 Pa < p(O2) < 22 kPa. The derived theoretical model considers the gas/solid kinetics for the TiO2/O2 system in terms of two diffusion regimes: the fast regime related to fast defects (oxygen vacancies and titanium interstitials) and leading to quasi-equilibrium, and the slow regime associated with slow defects (titanium vacancies) resulting in the gas/solid equilibrium. It has been shown that incorporation of donor-type elements, such as niobium, and imposition of oxygen activity above a certain critical value, results in a substantial reduction in the concentration of high mobility defects and leads to slowing down the equilibration kinetics. In consequence, the fast kinetic regime is not observed. Comparison of the kinetic data for Nb-doped TiO2 single crystal (this work) and polycrystalline Nb-doped TiO2 (reported before) indicates that the gas/solid kinetics for the polycrystalline specimen at higher oxygen activities is rate controlled by the transport of oxygen within individual grains.}, number={34}, journal={The Journal of Physical Chemistry A}, publisher={American Chemical Society (ACS)}, author={Nowotny, Janusz and Bak, Tadeusz and Dickey, Elisabeth C and Sigmund, Wolfgang and Alim, Mohammad A.}, year={2016}, month={Aug}, pages={6822–6837} }
 @article{burch_fancher_patala_dickey_2016, title={Imaging 180° Polarization Reversal in Ferroelectric Oxides with Electron Backscatter Diffraction}, volume={22}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/s1431927616009958}, DOI={10.1017/s1431927616009958}, number={S3}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Burch, Matthew J. and Fancher, Chris M. and Patala, Srikanth and Dickey, Elizabeth C.}, year={2016}, month={Jul}, pages={1822–1823} }
 @article{ascienzo_yuan_greenbaum_bayer_maier_wang_randall_dickey_zhao_ren_et al._2016, title={Investigation of Electric Field–Induced Structural Changes at Fe-Doped SrTiO3 Anode Interfaces by Second Harmonic Generation}, volume={9}, ISSN={1996-1944}, url={http://dx.doi.org/10.3390/ma9110883}, DOI={10.3390/ma9110883}, abstractNote={We report on the detection of electric field–induced second harmonic generation (EFISHG) from the anode interfaces of reduced and oxidized Fe-doped SrTiO3 (Fe:STO) single crystals. For the reduced crystal, we observe steady enhancements of the susceptibility components as the imposed dc-voltage increases. The enhancements are attributed to a field-stabilized electrostriction, leading to Fe:Ti-O bond stretching and bending in Fe:Ti-O6 octahedra. For the oxidized crystal, no obvious structural changes are observed below 16 kV/cm. Above 16 kV/cm, a sharp enhancement of the susceptibilities occurs due to local electrostrictive deformations in response to oxygen vacancy migrations away from the anode. Differences between the reduced and oxidized crystals are explained by their relative oxygen vacancy and free carrier concentrations which alter internal electric fields present at the Pt/Fe:STO interfaces. Our results show that the optical SHG technique is a powerful tool for detecting structural changes near perovskite-based oxide interfaces due to field-driven oxygen vacancy migration.}, number={11}, journal={Materials}, publisher={MDPI AG}, author={Ascienzo, D. and Yuan, H. C. and Greenbaum, S. and Bayer, T. J. M. and Maier, R. A. and Wang, J. J. and Randall, C. A. and Dickey, Elizabeth C. and Zhao, H. B. and Ren, Y. H. and et al.}, year={2016}, month={Oct}, pages={883} }
 @article{harris_burch_mily_dickey_maria_2016, title={Microstructure and dielectric properties with CuO additions to liquid phase sintered BaTiO3 thin films}, volume={31}, ISSN={0884-2914 2044-5326}, url={http://dx.doi.org/10.1557/jmr.2016.89}, DOI={10.1557/jmr.2016.89}, number={8}, journal={Journal of Materials Research}, publisher={Cambridge University Press (CUP)}, author={Harris, David T. and Burch, Matthew J. and Mily, Edward J. and Dickey, Elizabeth C. and Maria, Jon-Paul}, year={2016}, month={Mar}, pages={1018–1026} }
 @article{serrano-zabaleta_larrea_larrañaga_dickey_2016, title={Microstructure, texture, and crystallography in Ni–GDC and Co–GDC porous cermets obtained from directionally solidified eutectic ceramics}, volume={52}, ISSN={0022-2461 1573-4803}, url={http://dx.doi.org/10.1007/s10853-016-0225-9}, DOI={10.1007/s10853-016-0225-9}, abstractNote={Lamellar NiO–GDC (Gadolinium-doped Ceria) and CoO–GDC directionally solidified eutectic ceramics (DSECs) were produced by the laser floating-zone technique and subjected to reduction in order to obtain porous cermets of Ni–GDC and Co–GDC, which have potential applications as anodes in solid oxide fuel cells (SOFC). The reduction of these DSECs into porous cermets was studied at 650 °C in NiO–GDC and at 500 and 700 °C in CoO–GDC, all of them processed with similar reduction kinetics. In comparison to similar Ni–YSZ and Co–YSZ lamellar cermets previously studied, no sharp reduction front was observed. The interface between the reduced and nonreduced zones is broader, with pores homogenously distributed in wide areas. Afterwards, the microstructure, texture, and crystallography of the samples were studied by electron microscopy as well as by electron and X-ray diffraction when completely reduced. The single crystal NiO and CoO lamellae transformed into porous polycrystalline metallic lamellae. Moreover, microscopy observations revealed a porous nanostructure of Co particles obtained by reduction at low temperatures (500 °C). Many of the Co and Ni particles seemed to have roughly maintained the previous crystallographic orientation with respect to the GDC phase, although the disorder of the crystallographic orientation increased significantly. In addition, a significant amount of the Ni particles reoriented to form an epitaxial interface with the (100)–GDC surface.}, number={10}, journal={Journal of Materials Science}, publisher={Springer Nature}, author={Serrano-Zabaleta, S. and Larrea, A. and Larrañaga, A. and Dickey, E. C.}, year={2016}, month={Jul}, pages={5477–5488} }
 @article{garten_burch_gupta_haislmaier_gopalan_dickey_trolier-mckinstry_2016, title={Relaxor Ferroelectric Behavior in Barium Strontium Titanate}, volume={99}, ISSN={0002-7820}, url={http://dx.doi.org/10.1111/jace.14109}, DOI={10.1111/jace.14109}, abstractNote={The development of barium strontium titanate-based tunable dielectrics is currently hindered by high losses in the paraelectric phase. Barium strontium titanate (BST) thin films and ceramics show a range of ferroelectric transition behavior, from normal, diffuse, and relaxor-like ferroelectric responses, depending on the sample preparation route. Rayleigh analysis, the temperature-dependent dielectric response, and the optical second harmonic generation were used to characterize the ferroelectric response of bulk and thin film BST. Ferroelectricity is observed to persist in BST for 30°C above the global phase transition temperature in ceramics and over 50°C in thin films. Piezoresponse force microscopy on BST ceramics with extensive residual ferroelectricity reveals the coexistence of nanoscale polar regions, typical of relaxor ferroelectrics, as well as micrometer scale domain structures. The nature of the phase transition was probed using electron energy loss spectroscopy and found to correlated with the nanoscale A-site chemical inhomogeneity in the samples.}, number={5}, journal={Journal of the American Ceramic Society}, publisher={Wiley}, author={Garten, Lauren M. and Burch, Matthew and Gupta, Arnab Sen and Haislmaier, Ryan and Gopalan, Venkataraman and Dickey, Elizabeth C. and Trolier-McKinstry, Susan}, editor={Brennecka, G. L.Editor}, year={2016}, month={Feb}, pages={1645–1650} }
 @article{bayer_wang_carter_moballegh_baker_irving_dickey_chen_randall_2016, title={The relation of electrical conductivity profiles and modulus data using the example of STO:Fe single crystals: A path to improve the model of resistance degradation}, volume={117}, ISSN={1359-6454}, url={http://dx.doi.org/10.1016/j.actamat.2016.07.024}, DOI={10.1016/j.actamat.2016.07.024}, abstractNote={Resistance degradation in perovskites is characterized by an increase in current over time with applied electric field. This behavior can be simulated and spatially resolved conductivity profiles can be measured, but some inconsistencies remain. A new approach to address these problems is presented that utilizes time-resolved impedance spectroscopy with an applied DC voltage to provide new insight into the resistance degradation phenomenon. In particular, this method allows the in-situ acquisition of spatio-temporal variations in conductivity. In SrTiO3 a single bulk-dominated maximum of the imaginary part of the modulus M″ transitions to two maxima during degradation, reflecting the hole conductivity in the anode region and the electron conductivity in the cathode region. To clarify the influence of conductivity profiles on impedance data, the reversed route is presented by using simulated conductivity profiles to calculate impedance data. It will be emphasized that this methodology is not limited to the perovskite system considered here, but can be adapted to any kind of system characterized by a spatially varying conductivity.}, journal={Acta Materialia}, publisher={Elsevier BV}, author={Bayer, Thorsten J.M. and Wang, Jian-Jun and Carter, Jared J. and Moballegh, Ali and Baker, Jonathon and Irving, Douglas L. and Dickey, Elizabeth C. and Chen, Long-Qing and Randall, Clive A.}, year={2016}, month={Sep}, pages={252–261} }
 @article{moballegh_rost_maria_dickey_2015, title={Chemical Homogeneity in Entropy-Stabilized Complex Metal Oxides}, volume={21}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927615007539}, DOI={10.1017/S1431927615007539}, abstractNote={Innovation in new mixtures of constituents can lead to discover exciting new materials with unexpected properties and revolutionary applications [1,2]. It is known, the Gibbs energy needs to be minimized, as the main requirement, to achieve a stable single phase compound. Conventional approach to minimize the total energy of system is searching for a large and negative enthalpy. However, in this work, we show that the phase stability can be reached where the configurational entropy is maximized with mixing as many diverse elements as possible.}, number={S3}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Moballegh, Ali and Rost, Christina M. and Maria, Jon-Paul and Dickey, Elizabeth C.}, year={2015}, month={Aug}, pages={1349–1350} }
 @article{chen_dickey_2015, title={Crystallographic Orientation and Deformation Mechanisms of Laser-processed Directionally Solidified WC-W2C Eutectoids}, volume={21}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927615003840}, DOI={10.1017/S1431927615003840}, abstractNote={An abstract is not available for this content so a preview has been provided. As you have access to this content, a full PDF is available via the ‘Save PDF’ action button.}, number={S3}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Chen, Wei-Ting and Dickey, Elizabeth C.}, year={2015}, month={Aug}, pages={609–610} }
 @article{burch_harris_fancher_maria_dickey_2015, title={Domain Structure of Bulk and Thin-Film Ferroelectrics By Transmission Kikuchi Diffraction}, volume={21}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/s1431927615004687}, DOI={10.1017/s1431927615004687}, number={S3}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Burch, Matthew J. and Harris, David T. and Fancher, Chris M. and Maria, Jon-Paul and Dickey, Elizabeth C.}, year={2015}, month={Aug}, pages={777–778} }
 @article{daubert_lewis_gotsch_mundy_monroe_dickey_losego_parsons_2015, title={Effect of Meso- and Micro-Porosity in Carbon Electrodes on Atomic Layer Deposition of Pseudocapacitive V2O5 for High Performance Supercapacitors}, volume={27}, ISSN={0897-4756 1520-5002}, url={http://dx.doi.org/10.1021/acs.chemmater.5b01602}, DOI={10.1021/acs.chemmater.5b01602}, abstractNote={Atomic layer deposition (ALD) of vanadium oxide is a viable means to add pseudocapacitive layers to porous carbon electrodes. Two commercial activated carbon materials with different surface areas and pore structures were acid treated and coated by V2O5 ALD using vanadium triisopropoxide and water at 150 °C. The V2O5 ALD process was characterized at various temperatures to confirm saturated ALD growth conditions. Capacitance and electrochemical impedance analysis of subsequently constructed electrochemical capacitors (ECs) showed improved charge storage for the ALD coated electrodes, but the extent of improvement depended on initial pore structure. The ALD of V2O5 onto mesoporous carbon increased the capacitance by up to 46% after 75 ALD cycles and obtained a maximum pseudocapacitance of 540 F/g(V2O5) after 25 ALD cycles, while maintaining low electrical resistance, high columbic efficiency, and a high cycle life. However, adding V2O5 ALD to microporous carbons with pore diameters of <11 Å showed far less improvement, likely due to “blocking off” of the micropores and reducing the accessible surface area. Results show that ALD is a viable means to construct high-performance supercapacitors from activated carbon which is the basis for commercial products, and a clear understanding of carbon electrode pore structure, layer conformality, and layer thickness are necessary to fully optimize performance.}, number={19}, journal={Chemistry of Materials}, publisher={American Chemical Society (ACS)}, author={Daubert, James S. and Lewis, Neal P. and Gotsch, Hannah N. and Mundy, J. Zachary and Monroe, David N. and Dickey, Elizabeth C. and Losego, Mark D. and Parsons, Gregory N.}, year={2015}, month={Sep}, pages={6524–6534} }
 @article{moballegh_dickey_2015, title={Electric-field-induced point defect redistribution in single-crystal TiO2– and effects on electrical transport}, volume={86}, ISSN={1359-6454}, url={http://dx.doi.org/10.1016/j.actamat.2014.11.032}, DOI={10.1016/j.actamat.2014.11.032}, abstractNote={The spatial redistribution of non-stoichiometric point defects in rutile TiO2 is studied as a function of voltage and time. Single crystals are equilibrated initially to a well-defined stoichiometry with n-type conductivity and a carrier concentration on the order of 1018 cm−3. The crystals are subsequently electroded with Pt contacts that exhibit Schottky behavior. When subjected to an applied voltage of 15 V, a time-dependent increase and saturation in the leakage current is observed, which is associated with an accumulation of point defects and an attendant decrease in stoichiometry at the cathode electrode. This local change in stoichiometry degrades the Schottky barrier, leading to asymmetric electrodes and thus macroscopic rectifying behavior. Cathodoluminescence spectroscopy shows that Ti interstitials dominate the point defect redistribution process. Under larger applied voltages, of around 30 V, qualitatively different behavior is observed in which the resistivity increases as a function of time. This behavior is associated with condensation of point defects into a region of extended defects and Magnéli phases near the cathode, sufficient to increase the bulk stoichiometry and resistivity. These experiments demonstrate that a one-dimensional drift-diffusion process, as opposed to filamentary growth, dominates in these experimental conditions and that the Pt–TiO2–Pt system remains closed, with no significant oxygen transport across the Pt–TiO2 interfaces. We believe this is the first observation of a second higher-voltage regime in which the bulk stoichiometry and thus resistivity is increased as large concentrations of defects condense into metallic Magnéli phases in the near-electrode regions.}, journal={Acta Materialia}, publisher={Elsevier BV}, author={Moballegh, Ali and Dickey, Elizabeth C.}, year={2015}, month={Mar}, pages={352–360} }
 @article{rost_sachet_borman_moballegh_dickey_hou_jones_curtarolo_maria_2015, title={Entropy-stabilized oxides}, volume={6}, ISSN={2041-1723}, url={http://dx.doi.org/10.1038/ncomms9485}, DOI={10.1038/ncomms9485}, abstractNote={Abstract Configurational disorder can be compositionally engineered into mixed oxide by populating a single sublattice with many distinct cations. The formulations promote novel and entropy-stabilized forms of crystalline matter where metal cations are incorporated in new ways. Here, through rigorous experiments, a simple thermodynamic model, and a five-component oxide formulation, we demonstrate beyond reasonable doubt that entropy predominates the thermodynamic landscape, and drives a reversible solid-state transformation between a multiphase and single-phase state. In the latter, cation distributions are proven to be random and homogeneous. The findings validate the hypothesis that deliberate configurational disorder provides an orthogonal strategy to imagine and discover new phases of crystalline matter and untapped opportunities for property engineering.}, number={1}, journal={Nature Communications}, publisher={Springer Science and Business Media LLC}, author={Rost, Christina M. and Sachet, Edward and Borman, Trent and Moballegh, Ali and Dickey, Elizabeth C. and Hou, Dong and Jones, Jacob L. and Curtarolo, Stefano and Maria, Jon-Paul}, year={2015}, month={Sep} }
 @article{chen_meredith_dickey_2015, title={Growth and Microstructure-Dependent Hardness of Directionally Solidified WC-W2C Eutectoid Ceramics}, volume={98}, ISSN={0002-7820}, url={http://dx.doi.org/10.1111/jace.13561}, DOI={10.1111/jace.13561}, abstractNote={Directionally solidified WC–W2C ceramics containing 40 at% carbon, corresponding to the WC–W2C eutectoid composition, were produced by laser surface melt processing. The resulting microstructures showed a lamellar-type eutectic/eutectoid microstructure with the WC minor phase embedded in the W2C matrix phase. The interlamellar spacing (λ) in the eutectoid regions followed the relationship Vλ3.8 = constant, with the smallest spacing of 331 ± 36 nm achieved in the 3.24 mm/s processed sample. The indentation hardness increased with decreasing interlamellar spacing, and a Vickers indentation hardness of 28.5 GPa was achieved in the sample with the smallest interlamellar spacing. The directionally solidified WC–W2C materials show enhanced indentation mechanical properties in comparison to previously reported WC–Co composites and WC-based materials.}, number={7}, journal={Journal of the American Ceramic Society}, publisher={Wiley}, author={Chen, Wei-Ting and Meredith, Caleb H. and Dickey, Elizabeth C.}, editor={Trice, R.Editor}, year={2015}, month={Mar}, pages={2191–2196} }
 @article{cheng_miao_qin_li_xu_haftbaradaran_dickey_gao_zhu_2015, title={Large anelasticity and associated energy dissipation in single-crystalline nanowires}, volume={10}, ISSN={1748-3387 1748-3395}, url={http://dx.doi.org/10.1038/NNANO.2015.135}, DOI={10.1038/nnano.2015.135}, number={8}, journal={Nature Nanotechnology}, publisher={Springer Science and Business Media LLC}, author={Cheng, Guangming and Miao, Chunyang and Qin, Qingquan and Li, Jing and Xu, Feng and Haftbaradaran, Hamed and Dickey, Elizabeth C. and Gao, Huajian and Zhu, Yong}, year={2015}, month={Jul}, pages={687–691} }
 @article{harris_burch_li_dickey_maria_2015, title={Low‐Temperature Control of Twins and Abnormal Grain Growth in BaTiO
            3}, volume={98}, ISSN={0002-7820 1551-2916}, url={http://dx.doi.org/10.1111/jace.13643}, DOI={10.1111/jace.13643}, abstractNote={The microstructure of polycrystalline barium titanate (BaTiO3) thin films processed with a liquid-phase can be controlled by the crystallographic orientation of the underlying sapphire substrate. During postdeposition crystallization, the tendency for {111} twin nucleation, which drives subsequent abnormal grain growth, depends upon the specific sapphire facet. Specifically, tilting away from the close-packed c-plane modifies the orientation, morphology, and relative amount of an interfacial BaAl2O4 second phase. These factors control the density of twin formation, and thus overall grain size of the crystallized BaTiO3. As the substrate orientation transitions from c-plane, to r-plane, to a-plane, the twin density is reduced, the average grain size decreases systematically from 270 to 130 nm, and the grain structure becomes overall more homogeneous. This twinning mechanism and abnormal grain growth occur by 900°C, several hundred degrees lower than reported previously.}, number={8}, journal={Journal of the American Ceramic Society}, publisher={Wiley}, author={Harris, David T. and Burch, Matthew J. and Li, Jing and Dickey, Elizabeth C. and Maria, Jon‐Paul}, editor={Viehland, D.Editor}, year={2015}, month={May}, pages={2381–2387} }
 @article{hu_li_darling_wang_vanleeuwen_liu_kecskes_dickey_liu_2015, title={Nano-sized Superlattice Clusters Created by Oxygen Ordering in Mechanically Alloyed Fe Alloys}, volume={5}, ISSN={2045-2322}, url={http://dx.doi.org/10.1038/srep11772}, DOI={10.1038/srep11772}, abstractNote={Creating and maintaining precipitates coherent with the host matrix, under service conditions is one of the most effective approaches for successful development of alloys for high temperature applications; prominent examples include Ni- and Co-based superalloys and Al alloys. While ferritic alloys are among the most important structural engineering alloys in our society, no reliable coherent precipitates stable at high temperatures have been found for these alloys. Here we report discovery of a new, nano-sized superlattice (NSS) phase in ball-milled Fe alloys, which maintains coherency with the BCC matrix up to at least 913 °C. Different from other precipitates in ferritic alloys, this NSS phase is created by oxygen-ordering in the BCC Fe matrix. It is proposed that this phase has a chemistry of Fe3O and a D03 crystal structure and becomes more stable with the addition of Zr. These nano-sized coherent precipitates effectively double the strength of the BCC matrix above that provided by grain size reduction alone. This discovery provides a new opportunity for developing high-strength ferritic alloys for high temperature applications.}, number={1}, journal={Scientific Reports}, publisher={Springer Science and Business Media LLC}, author={Hu, Yong-Jie and Li, Jing and Darling, Kristopher A. and Wang, William Y. and VanLeeuwen, Brian K. and Liu, Xuan L. and Kecskes, Laszlo J. and Dickey, Elizabeth C. and Liu, Zi-Kui}, year={2015}, month={Jul} }
 @article{liu_liu_wu_miller_dickey_2015, title={Visualization of film-forming polymer particles with a liquid cell technique in a transmission electron microscope}, volume={140}, ISSN={0003-2654 1364-5528}, url={http://dx.doi.org/10.1039/c5an01067e}, DOI={10.1039/c5an01067e}, abstractNote={Liquid cell transmission electron microscopy technique provides the opportunity to image room-temperature film-forming polymer particles in solution. Together with staining technique, it can also be used as a tool to characterize the internal structure of polymer particles <italic>in situ</italic>.}, number={18}, journal={The Analyst}, publisher={Royal Society of Chemistry (RSC)}, author={Liu, Lili and Liu, Yi and Wu, Wenjun and Miller, Christopher. M. and Dickey, Elizabeth C.}, year={2015}, pages={6330–6334} }
 @article{burch_li_garten_sang_lebeau_trolier-mckinstry_maria_dickey_2014, title={Investigation of Local A-site Chemistry in Barium Strontium Titanate Using Aberration Corrected STEM, EELS and EDS}, volume={20}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927614011696}, DOI={10.1017/S1431927614011696}, abstractNote={Barium strontium titante (BST) is an important dielectric material because of its high tunability (dielectric constant as a function of applied voltage) and low loss, with specific applications in tunable microwave circuits. However, regardless of processing technique, additives, or synthesis temperatures some remnant ferroelectricity is always observed beyond the paraelectric phase transition [1]. One possible explanation for this remnant ferroelectricity, which has been hotly debated, is that the local stoichiometry of the A-site cations (Ba and Sr) is not globally and locally homogeneous. This hypothesis surmises that local areas, which are barium rich, may result in remnant polarization [1]. However, this hypothesis has never been experimentally shown. In this work, we use an aberration corrected scanning transmission electron microscope (STEM), electron energy loss spectroscopy (EELS), and energy dispersive X-ray spectroscopy (EDS) to investigate the local stoichiometry of arguably the bestengineered barium strontium titanate samples ever fabricated [2] in comparison to BST thin films showing some of the best tunability in thin-film form.}, number={S3}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Burch, Matthew J. and Li, Jing and Garten, Lauren and Sang, Xiahan and Lebeau, James and Trolier-Mckinstry, Susan and Maria, Jon-Paul and Dickey, Elizabeth C.}, year={2014}, month={Aug}, pages={1992–1993} }
 @article{moballegh_dickey_2014, title={Investigation of the Nature and Mechanism of Resistive Switching in TiO2-x}, volume={20}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927614011258}, DOI={10.1017/s1431927614011258}, abstractNote={The spatial redistribution of the charged point defects under direct-current (DC) biasing can have significant implications for electroceramic device performance and lifetime [1,2]. The transport behavior of point defects is regulated by the boundary conditions of the electrodes, which can block ion transfer across the interface to varying degrees. When the electrodes are impermeable to mass transport, there will be an accumulation of point defects in the near-electrode region that can lead to significant modifications in the local electronic carrier concentrations at the interface. Such defect redistribution is responsible for the long-term increases in leakage current in many capacitor devices. On the other hand, this same phenomena can lead to resistive switching behavior via modification of the interface Schottky barrier at the reverse-biased cathode [1-4].}, number={S3}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Moballegh, Ali and Dickey, Elizabeth C.}, year={2014}, month={Aug}, pages={1904–1905} }
 @article{white_dickey_2014, title={Mechanical properties and deformation mechanisms of B4C–TiB2 eutectic composites}, volume={34}, ISSN={0955-2219}, url={http://dx.doi.org/10.1016/j.jeurceramsoc.2013.08.012}, DOI={10.1016/j.jeurceramsoc.2013.08.012}, abstractNote={Samples of B4C–TiB2 eutectic are laser processed to produce composites with varying microstructural scales. The eutectic materials exhibit both load dependent and load independent hardness regimes with a transition occurring between 4 and 5 N indentation load. The load-independent hardness of eutectics with a microstructural scale smaller than 1 μm is about 31 GPa, and the indentation fracture toughness (5–10 N indenter load) of the eutectics is 2.47–4.76 MPa m1/2. Indentation-induced cracks are deflected by TiB2 lamellae, and indentation-induced spallation is reduced in the B4C–TiB2 eutectic compared to monolithic B4C. Indentation-induced amorphization in monolithic B4C and the B4C phase of the eutectic is detected using Raman spectroscopy. Sub-surface damage is observed using TEM, including microcracking and amorphization damage in B4C and B4C–TiB2 eutectics. Dislocations are observed in the TiB2 phase of eutectics with an interlamellar spacing of 1.9 μm.}, number={9}, journal={Journal of the European Ceramic Society}, publisher={Elsevier BV}, author={White, Ryan M. and Dickey, Elizabeth C.}, year={2014}, month={Aug}, pages={2043–2050} }
 @article{burch_li_harris_maria_dickey_2014, title={Mechanisms for microstructure enhancement in flux-assisted growth of barium titanate on sapphire}, volume={29}, ISSN={0884-2914 2044-5326}, url={http://dx.doi.org/10.1557/jmr.2014.59}, DOI={10.1557/jmr.2014.59}, number={7}, journal={Journal of Materials Research}, publisher={Cambridge University Press (CUP)}, author={Burch, Matthew J. and Li, Jing and Harris, David T. and Maria, Jon-Paul and Dickey, Elizabeth C.}, year={2014}, month={Mar}, pages={843–848} }
 @article{dickey_berger_merino_goto_2014, title={Special Issue: Directionally Solidified Eutectics: Selected Papers from DSEC IV Preface}, volume={34}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000335872500001&KeyUID=WOS:000335872500001}, DOI={10.1016/j.jeurceramsoc.2014.02.005}, number={9}, journal={Journal of the European Ceramic Society}, author={Dickey, Elizabeth C. and Berger, Marie-Helene and Merino, Rosa I. and Goto, Takashi}, year={2014}, pages={2041} }
 @article{harris_lam_burch_li_rogers_dickey_maria_2014, title={Ultra-high tunability in polycrystalline Ba1−xSrxTiO3 thin films}, volume={105}, ISSN={0003-6951 1077-3118}, url={http://dx.doi.org/10.1063/1.4893615}, DOI={10.1063/1.4893615}, abstractNote={Ba0.7Sr0.3TiO3 thin polycrystalline films with an ultra-high capacitance tunability approaching 5:1 at 175 kV/cm were made possible by a flux-assisted synthesis approach. In this process, a small volume fraction of a low melting temperature glass is added during low-temperature sputter deposition. Subsequent annealing activates the liquid phase, which in turn provides the mass transport needed to approach full density, to increase grain size, and to improve crystallinity, and, in so doing, achieves a stronger non-linear dielectric response. Ba0.7Sr0.3TiO3 films with 0%, 1%, 4%, and 7% BaO-3B2O3 flux exhibited grain sizes of 25 nm, 28 nm, 48 nm, and 56 nm, and dielectric tunabilities of 25%, 33%, 64%, and 80% respectively. These values represent substantial improvements when compared to conventionally processed tunable dielectric films.}, number={7}, journal={Applied Physics Letters}, publisher={AIP Publishing}, author={Harris, D. T. and Lam, P. G. and Burch, M. J. and Li, J. and Rogers, B. J. and Dickey, E. C. and Maria, J.-P.}, year={2014}, month={Aug}, pages={072904} }
 @article{andre_zhang_gutierrez_dickey_samarth_mohney_2013, title={Characterization of Zn1−xMnxSe nanowires and nanoribbons with cation sublattice ordering}, volume={375}, ISSN={0022-0248}, url={http://dx.doi.org/10.1016/j.jcrysgro.2013.04.025}, DOI={10.1016/j.jcrysgro.2013.04.025}, abstractNote={Characterization of Zn1−xMnxSe nanowires grown by Au-catalyzed chemical vapor deposition (CVD) using transmission electron microscopy is reported. The nanostructures were found to grow in the form of nanowires, nanoribbons, and nanosaws. The fraction of manganese on the cation sublattice in the nanowires varied from x=0.1 to x=0.28. No correlation between Mn fraction and nanowire diameter was found for straight nanowires; however, in tapered nanowires the Mn fraction was found to increase as the diameter increased. The tapering, as well as the increase in Mn fraction, is likely caused by thin film deposition with a higher Mn fraction on the sides of the nanowires. Some of the nanoribbons were found to display extra diffraction spots at half-order positions in selected area diffraction. The half-order reflections were found to have originated from spontaneous atomic ordering of Mn and Zn on planes on the cation sublattice.}, journal={Journal of Crystal Growth}, publisher={Elsevier BV}, author={Andre, K.L. and Zhang, D.M. and Gutierrez, H.R. and Dickey, E.C. and Samarth, N.S. and Mohney, S.E.}, year={2013}, month={Jul}, pages={95–99} }
 @inproceedings{shen_yu_wang_ramirez_li_ke_kendrick_podraza_jackson_dickey_et al._2013, title={Effect of c-Si Doping Density on Heterojunction with Intrinsic Thin Layer (HIT) Radial Junction Solar Cells}, url={https://app.dimensions.ai/details/publication/pub.1094675102}, DOI={10.1109/PVSC.2013.6744975}, abstractNote={Radial junction Si pillar array solar cells based on the heterojunction with intrinsic thin layer (HIT) structure were fabricated from p-type crystal Si (c-Si) wafers of different doping densities. The HIT structure consisting of intrinsic/n-type hydrogenated amorphous Si (a-Si:H) deposited by plasma-enhanced chemical vapor deposition (PECVD) at low temperature (200°C) was found to effectively passivate the high surface area of the p-type Si pillar arrays resulting in open circuit voltages (Voc>0.5) comparable to that obtained on planar devices. At high c-Si doping densities (>1018 cm-3), the short-circuit current density (Jsc) and energy conversion efficiency of the radial junction devices were higher than those of the planar devices demonstrating improved carrier collection in the radial junction structure.}, booktitle={Conference Record IEEE Photovoltaic Specialists Conference}, author={Shen, H and Yu, Y and Wang, X and Ramirez, JI and Li, YV and Ke, Y and Kendrick, CE and Podraza, NJ and Jackson, TN and Dickey, EC and et al.}, year={2013}, pages={2466–2469} }
 @article{shen_yuwen_wang_ramirez_li_ke_kendrick_podraza_jackson_dickey_et al._2013, title={Effect of c-Si Doping Density on Heterojunction with Intrinsic Thin Layer (HIT) Radial Junction Solar Cells}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000340054100559&KeyUID=WOS:000340054100559}, journal={2013 Ieee 39th Photovoltaic Specialists Conference (Pvsc)}, author={Shen, Haoting and Yuwen, Yu and Wang, Xin and Ramirez, J. Israel. and Li, Yuanyuan V. and Ke, Yue and Kendrick, Chito E. and Podraza, Nikolas J. and Jackson, Thomas N. and Dickey, Elizabeth C. and et al.}, year={2013}, pages={2466–2469} }
 @article{moballegh_dickey_2013, title={Electric Field-Induced Point Defect Redistribution in TiO2}, volume={19}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927613011914}, DOI={10.1017/s1431927613011914}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.}, number={S2}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Moballegh, A. and Dickey, E.C.}, year={2013}, month={Aug}, pages={1984–1985} }
 @article{sloppy_lu_dickey_macdonald_2013, title={Growth mechanism of anodic tantalum pentoxide formed in phosphoric acid}, volume={87}, ISSN={0013-4686}, url={http://dx.doi.org/10.1016/j.electacta.2012.08.014}, DOI={10.1016/j.electacta.2012.08.014}, abstractNote={The formation of anodic tantalum oxide (Ta2O5) in dilute phosphoric acid is quantitatively described using point defect chemistry reactions. Oxide formed in phosphoric acid has a distinct bi-layer structure, where the inner layer is pure Ta2O5, but the outer layer contains phosphate incorporated from the solution. In the point defect model (PDM) presented herein, the inner layer forms directly from, and grows into the metal, due to the production of oxygen vacancies at the metal/oxide interface. The outer layer forms due to the production of tantalum interstitials at the metal/oxide interface and their subsequent migration to the oxide/solution interface, where they hydrolyze to form Ta2O5. The Faradaic impedance is derived for the point defect reactions, and a bi-layer equivalent electrical analog is used to optimize the model to the measured electrochemical impedance spectroscopy (EIS) data. The oxide thickness and ionic current density have been measured separately, and the PDM parameters correctly predict the oxide thickness and ionic current densities due to the production of tantalum interstitials and oxygen vacancies.}, journal={Electrochimica Acta}, publisher={Elsevier BV}, author={Sloppy, J.D. and Lu, Z. and Dickey, E.C. and Macdonald, D.D.}, year={2013}, month={Jan}, pages={82–91} }
 @article{li_burch_harris_maria_dickey_2013, title={Interface Evolution of Flux-Grown BaTiO3 Thin Films on Sapphire Substrates}, volume={19}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927613011422}, DOI={10.1017/S1431927613011422}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2013 in Indianapolis, Indiana, USA, August 4 – August 8, 2013.}, number={S2}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Li, J. and Burch, M. and Harris, D.T. and Maria, J.-P. and Dickey, E.C.}, year={2013}, month={Aug}, pages={1886–1887} }
 @article{white_kunkle_haines_dickey_2013, title={Plasma Processing of B4C-TiB2 Eutectic Composite Powders}, volume={96}, ISSN={0002-7820}, url={http://dx.doi.org/10.1111/jace.12431}, DOI={10.1111/jace.12431}, abstractNote={The production of a composite powder of eutectic B4C–TiB2 is demonstrated via an atmospheric plasma processing method. Feedstock material is prepared for plasma processing by mixing and spray drying monolithic B4C and TiB2 to produce a flowable precursor powder. These powders are fed through a plasma torch, where they are melted and actively quenched in flight with argon gas. Plasma processed powders are composed of crystalline B4C and TiB2, with some additional B2O3 oxide phase. The plasma processing method results in the production of monolithic B4C and TiB2 nanoparticles, but some larger particles (generally ≥10 μm in diameter) are shown to contain the traditional lamellar eutectic microstructure. The eutectic interphase spacing ranges from 100 to 650 nm, and the composite microstructure is present through the entire thickness of the eutectic particles. Future work on plasma processing of eutectic powders should focus on methods utilizing passive in-flight quenching to increase the average particle size.}, number={7}, journal={Journal of the American Ceramic Society}, publisher={Wiley}, author={White, Ryan M. and Kunkle, Jamie M. and Haines, Chris and Dickey, Elizabeth C.}, editor={Fahrenholt, W. G.Editor}, year={2013}, month={Jun}, pages={2050–2053} }
 @article{harris_burch_ihlefeld_lam_li_dickey_maria_2013, title={Realizing strain enhanced dielectric properties in BaTiO3 films by liquid phase assisted growth}, volume={103}, ISSN={0003-6951 1077-3118}, url={http://dx.doi.org/10.1063/1.4813270}, DOI={10.1063/1.4813270}, abstractNote={The addition of a liquid-forming flux to barium titanate thin films promotes densification and grain growth, improves nonlinear dielectric properties, and allows residual strain to be sustained in polycrystalline films without cracking at thicknesses relevant to device fabrication. Relative tuning, an excellent indicator of crystalline quality and an important material property for tunable microwave devices, increases from 20% to 70%. Films exhibit 0.15% residual differential thermal expansion mismatch strain, resulting in a shift to the paraelectric-ferroelectric phase transition of 50 °C. This result is in excellent agreement with theory, demonstrating the ability to tune ferroic transitions without epitaxial approaches.}, number={1}, journal={Applied Physics Letters}, publisher={AIP Publishing}, author={Harris, David T. and Burch, Matthew J. and Ihlefeld, Jon F. and Lam, Peter G. and Li, Jing and Dickey, Elizabeth C. and Maria, Jon-Paul}, year={2013}, month={Jul}, pages={012904} }
 @article{li_dickey_vanleeuwen_liu_darling_2012, title={Coherent, Oxygen-Rich Nano-Clusters In Fe-1at%Zr Alloy}, volume={18}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927612011294}, DOI={10.1017/S1431927612011294}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.}, number={S2}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Li, J. and Dickey, E.C. and VanLeeuwen, B.K. and Liu, Z. and Darling, K.A.}, year={2012}, month={Jul}, pages={1888–1889} }
 @article{podraza_gauntt_motyka_dickey_horn_2012, title={Electrical and optical properties of sputtered amorphous vanadium oxide thin films}, volume={111}, ISSN={0021-8979 1089-7550}, url={http://dx.doi.org/10.1063/1.3702451}, DOI={10.1063/1.3702451}, abstractNote={Amorphous vanadium oxide (VOx) is a component found in composite nanocrystalline VOx thin films. These types of composite films are used as thermistors in pulsed biased uncooled infrared imaging devices when containing face centered cubic vanadium monoxide phase crystallites, and substantial fractions of amorphous material in the composite are necessary to optimize device electrical properties. Similarly, optoelectronic devices exploiting the metal-to-semiconductor transition contain the room-temperature monoclinic or high-temperature (>68 °C) rutile vanadium dioxide phase. Thin films of VOx exhibiting the metal-to-semiconductor transition are typically polycrystalline or nanocrystalline, implying that significant amounts of disordered, amorphous material is present at grain boundaries or surrounding the crystallites and can impact the overall optical or electronic properties of the film. The performance of thin film material for either application depends on both the nature of the crystalline and amorphous components, and in this work we seek to isolate and study amorphous VOx. VOx thin films were deposited by pulsed dc reactive magnetron sputtering to produce amorphous materials with oxygen contents ≥2, which were characterized electrically by temperature dependent current-voltage measurements and optically characterized by spectroscopic ellipsometry. Film resistivity, thermal activation energy, and complex dielectric function spectra from 0.75 to 6.0 eV were used to identify the impact of microstructural variations including composition and density.}, number={7}, journal={Journal of Applied Physics}, publisher={AIP Publishing}, author={Podraza, N. J. and Gauntt, B. D. and Motyka, M. A. and Dickey, E. C. and Horn, M. W.}, year={2012}, month={Apr}, pages={073522} }
 @article{basantani_kozlowski_lee_li_dickey_jackson_bharadwaja_horn_2012, title={Enhanced electrical and noise properties of nanocomposite vanadium oxide thin films by reactive pulsed-dc magnetron sputtering}, volume={100}, ISSN={0003-6951 1077-3118}, url={http://dx.doi.org/10.1063/1.4731240}, DOI={10.1063/1.4731240}, abstractNote={Thin films of VOx (1.3 ≤ x ≤ 2) were deposited by reactive pulsed-dc magnetron sputtering of a vanadium metal target while RF-biasing the substrate. Rutherford back scattering, glancing angle x-ray, and cross-sectional transmission electron microscopy measurements revealed the formation of nanocolumns with nanotwins within VOx samples. The resistivity of nanotwinned VOx films ranged from 4 mΩ·cm to 0.6 Ω·cm and corresponding temperature coefficient of resistance between −0.1% and −2.6% per K, respectively. The 1/f electrical noise was analyzed in these VOx samples using the Hooge-Vandamme relation. These VOx films are comparable or surpass commercial VOx films deposited by ion beam sputtering.}, number={26}, journal={Applied Physics Letters}, publisher={AIP Publishing}, author={Basantani, H. A. and Kozlowski, S. and Lee, Myung-Yoon and Li, J. and Dickey, E. C. and Jackson, T. N. and Bharadwaja, S. S. N. and Horn, M.}, year={2012}, month={Jun}, pages={262108} }
 @article{burch_harris_white_moballegh_li_maria_dickey_2012, title={In situ heating studies of flux grown barium titanate thin films}, volume={18}, url={https://app.dimensions.ai/details/publication/pub.1054927598}, DOI={10.1017/s1431927612009245}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2012 in Phoenix, Arizona, USA, July 29 – August 2, 2012.}, number={S2}, journal={Microscopy and Microanalysis}, author={Burch, M.J. and Harris, D. and White, R.M. and Moballegh, A. and Li, J. and Maria, J.P. and Dickey, Elizabeth C.}, year={2012}, pages={1478–1479} }
 @article{ko_schulze_saint john_podraza_dickey_trolier-mckinstry_2012, title={Low Temperature Crystallization of Metastable Nickel Manganite Spinel Thin Films}, volume={95}, ISSN={0002-7820}, url={http://dx.doi.org/10.1111/j.1551-2916.2012.05201.x}, DOI={10.1111/j.1551-2916.2012.05201.x}, abstractNote={Single-phase metastable cubic spinel nickel manganite films, 0.5 ≤ Mn/(Mn+Ni) ≤ 0.8, were produced using chemical solution deposition. Of these, the sample with Mn/(Mn+Ni) = 0.80 showed the lowest electrical resistivity. Films annealed in Argon at 400°C for 5 h exhibit temperature coefficient of resistance values ranging from −3.81 to −3.93%/K and electrical resistivities of ~10 kΩ-cm. It was found by transmission electron microscopy that the metastable spinel phase appeared in both pyrolyzed and post-deposition annealed films. Spectroscopic ellipsometry measurements over the spectral range from 0.75 to 6.0 eV showed that the complex dielectric function spectra (ε = ε1 + iε2) varied as a function of the annealing conditions, due at least in part to changes in film density. Aging experiments have been used to identify variations in resistivity and temperature coefficient of resistance as functions of time to assess material stability. As a result, the aging coefficient was 6.5% for a film with Mn/(Ni+Mn) = 0.80 after aging at 150°C for 500 h.}, number={8}, journal={Journal of the American Ceramic Society}, publisher={Wiley}, author={Ko, Song Won and Schulze, Heidi M. and Saint John, David B. and Podraza, Nikolas J. and Dickey, Elizabeth C. and Trolier-McKinstry, Susan S.}, editor={Feteira, A.Editor}, year={2012}, month={May}, pages={2562–2567} }
 @article{motyka_gauntt_horn_dickey_podraza_2012, title={Microstructural evolution of thin film vanadium oxide prepared by pulsed-direct current magnetron sputtering}, volume={112}, ISSN={0021-8979 1089-7550}, url={http://dx.doi.org/10.1063/1.4759255}, DOI={10.1063/1.4759255}, abstractNote={Vanadium oxide (VOx) thin films have been deposited by pulsed-DC magnetron sputtering using a metallic vanadium target in a reactive argon and oxygen environment. While the process parameters (power, total pressure, oxygen-to-argon ratio) remained constant, the deposition time was varied to produce films between 75 ± 6 and 2901 ± 30 Å thick, which were then optically and electrically characterized. The complex dielectric function spectra (ε = ε1 + iε2) of the films from 0.75 to 5.15 eV were extracted by ex situ, multiple-angle spectroscopic ellipsometry (SE) measurements for the series of varied thickness VOx samples. Significant changes in ε and resistivity occur as a function of thickness, indicating the correlations exist between the electrical and the optical properties over this spectral range. In addition, in situ measurements via real time SE (RTSE) were made on the film grown to the largest thickness to track optical property and structural variations during growth. RTSE was also used to characterize changes in the film occurring after growth was completed, namely during post sputtering in the presence of argon and oxygen while the sample is shielded, and atmospheric exposure. RTSE indicates that the exposure of the film to the argon and oxygen environment, regardless of the shutter isolating the target, causes up to 200 Å of the top surface of the deposited film to become more electrically resistive as evidenced by variations in ε. Exposure of the VOx thin film to atmospheric conditions introduces a similar change in ε, but this change occurs throughout the bulk of the film. A combination of these observations with RTSE results indicates that thinner, less ordered VOx films are more susceptible to drastic changes due to atmospheric exposure and that microstructural variations in this material ultimately control its environmental stability.}, number={9}, journal={Journal of Applied Physics}, publisher={AIP Publishing}, author={Motyka, M. A. and Gauntt, B. D. and Horn, M. W. and Dickey, E. C. and Podraza, N. J.}, year={2012}, month={Nov}, pages={093504} }
 @article{stevenson_bittel_leh_li_dickey_lenahan_messing_2011, title={Color center formation in vacuum sintered Nd(3x)Y(3-3x)Al(5)O(12) transparent ceramics}, volume={98}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000286988400019&KeyUID=WOS:000286988400019}, DOI={10.1063/1.3549872}, abstractNote={Color center formation was studied in vacuum sintered Nd3xY3−3xAl5O12 transparent ceramics. The primary color centers were F- and F+-centers as evidenced by optical absorption in the 250–400 nm wavelength range and the presence of an electron spin resonance (ESR) line at g=1.9977. Annealing in air at 1600 °C for 10 h reduced the number of color centers to below the detection limit of ESR. Color center formation is controlled by oxidation and reduction of Fe2+/3+ impurities.}, number={5}, journal={Applied Physics Letters}, author={Stevenson, Adam J. and Bittel, Brad C. and Leh, Christopher G. and Li, Xin and Dickey, Elizabeth C. and Lenahan, Patrick M. and Messing, Gary L.}, year={2011} }
 @article{cabarcos_li_gauntt_antrazi_dickey_allara_horn_2011, title={Comparison of ion beam and magnetron sputtered vanadium oxide thin films for uncooled IR imaging}, volume={8012}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000294735100053&KeyUID=WOS:000294735100053}, DOI={10.1117/12.884377}, abstractNote={Uncooled Infrared (IR) focal plane arrays are an enabling technology for both military and commercial high sensitivity night vision cameras. IR imaging is accomplished using MEMS microbolometers fabricated on read-out integrated circuits and depends critically on the material used to absorb the incoming IR radiation. Suitable detector materials must exhibit a large temperature coefficient of resistance (TCR) and low noise characteristics to efficiently detect IR photons while also maintaining compatibility with standard integrated circuit (IC) processing. The most commonly used material in uncooled infrared imaging detectors is vanadium oxide deposited by reactive ion beam sputtering. Here we present a comparison of vanadium oxide thin films grown via commercial reactive ion beam sputtering to films grown using reactive pulsed DC magnetron sputtering. Films deposited using both methods were optically and structurally characterized using Raman spectroscopy, transmission electron microscopy, atomic force microscopy and grazing incidence X-ray diffraction. The measured electrical properties of the films were found to be very sensitive to the deposition conditions used. The ion beam sputtered films contained twinned FCC VO<sub>x</sub> nanocrystals with sub-nanometer twin spacing, in the form of large 10-20 nm wide columnar/conical grains. In contrast, the un-biased magnetron sputtered films consisted of equiax grains of FCC VO<sub>x</sub> (5-10 nm) encapsulated in an amorphous matrix. However, applying an RF bias to the sample substrate during the magnetron sputtering process, resulted in films that are similar in structure to ion beam deposited VO<sub>x</sub>. These differences in microstructure and composition were then correlated to the measured resistivities and TCRs of the films.}, number={ARTN 80121K}, journal={Infrared Technology and Applications Xxxvii}, author={Cabarcos, OM and Li, J and Gauntt, BD and Antrazi, S and Dickey, EC and Allara, DL and Horn, MW}, year={2011} }
 @article{samantaray_kaneda_qu_dickey_randall_2011, title={Effect of Firing Rates on Electrode Morphology and Electrical Properties of Multilayer Ceramic Capacitors}, volume={95}, ISSN={0002-7820}, url={http://dx.doi.org/10.1111/j.1551-2916.2011.04880.x}, DOI={10.1111/j.1551-2916.2011.04880.x}, abstractNote={Over the past decade, multilayer ceramic capacitors (MLCCs) have been able to achieve very high volumetric capacitance due to continuous improvement in their process technology. However, the performance of these devices is severely limited by the presence of electrode defects such as electrode porosity and roughness. To assess the effect of microstructure on MLCC performance, two sets of multilayer capacitors subjected to different processing conditions are compared for their microstructure and electrical properties. It is shown that more continuous and planar electrode morphology leads to lower local electric fields and thus, superior performance. These computational predictions are verified using electrical property measurements. Capacitors with higher electrode continuity exhibit proportionally higher capacitance, provided the grain-size distributions are similar. From the leakage current measurements, it is found that the Schottky barrier at the electrode–dielectric interface controls the conduction mechanism. This barrier height is adversely affected by the microstructural defects such as electrode discontinuities and roughness. These results are further supported by frequency-dependent impedance measurements.}, number={3}, journal={Journal of the American Ceramic Society}, publisher={Wiley}, author={Samantaray, M. M. and Kaneda, K. and Qu, W. and Dickey, E. C. and Randall, C. A.}, editor={Davies, P. K.Editor}, year={2011}, month={Oct}, pages={992–998} }
 @article{stevenson_li_martinez_anderson_suchy_kupp_dickey_mueller_messing_2011, title={Effect of SiO(2) on Densification and Microstructure Development in Nd:YAG Transparent Ceramics}, volume={94}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000290530200019&KeyUID=WOS:000290530200019}, DOI={10.1111/j.1551-2916.2010.04260.x}, abstractNote={This paper examines the influence of SiO2 doping on densification and microstructure evolution in Nd3xY3−3xAl5O12 (Nd:YAG) ceramics. Nd:YAG powders were doped with 0.035–0.28 wt% SiO2 and vacuum sintered between 1484° and 1750°C. 29Si magic-angle spinning nuclear magnetic resonance showed that Si4+ substitutes onto tetrahedrally coordinated Al3+ sites. High-resolution transmission electron microscopy showed no grain boundary second phases for all silica levels in samples sintered at 1600°–1750°C. Coarsening was limited by a solute drag mechanism as suggested by cubic grain growth kinetics and transmission electron microscopy energy-dispersive X-ray spectroscopy observations of increased Nd3+ concentration near grain boundaries. Increasing SiO2 content increased both densification and grain growth rate and led to increasingly coarsening-dominated sintering trajectories. Fine-grained (<3 μm), highly transparent (>82% real in-line transmission) ceramics were produced by sintering 0.035 wt% SiO2-doped ceramics at 1750°C for 8 h. Coarse-grained (18 μm), transparent samples were obtained with 0.28 wt% SiO2-doped Nd:YAG when sintered at 1600°C for 8 h.}, number={5}, journal={Journal of the American Ceramic Society}, author={Stevenson, Adam J. and Li, Xin and Martinez, Miguel A. and Anderson, Julie M. and Suchy, Daniel L. and Kupp, Elizabeth R. and Dickey, Elizabeth C. and Mueller, Karl T. and Messing, Gary L.}, year={2011}, pages={1380–1387} }
 @article{samantaray_gurav_dickey_randall_2011, title={Electrode Defects in Multilayer Capacitors Part I: Modeling the Effect of Electrode Roughness and Porosity on Electric Field Enhancement and Leakage Current}, volume={95}, ISSN={0002-7820}, url={http://dx.doi.org/10.1111/j.1551-2916.2011.04769.x}, DOI={10.1111/j.1551-2916.2011.04769.x}, abstractNote={Multilayer capacitors consist of multiple, often hundreds of capacitors connected in parallel to maximize volumetric efficiency. As the dielectric and electrode layer thicknesses are scaled down, microstructural imperfections become increasingly influential on the device electrical performance. Specifically, the presence of nonplanar and discontinuous electrodes can lead to local field enhancements while the relative morphologies of two adjacent electrodes determine variations in the local dielectric thickness. To study the effects of electrode morphologies, an analytical approach is taken to calculate the field enhancement and leakage current with respect to an ideal parallel-plate capacitor. It is shown that the electrode roughness causes the leakage current to increase with respect to that of the ideal flat parallel-plate capacitor. To further include the effects of local curvature on electric field enhancements, finite element methods are used to calculate field distributions within capacitor structures containing rough interfaces and porosity. In these simulations, the effects of electrode pore diameters, dielectric layer thickness, and the amplitude and wavelength of the electrode roughness are studied.}, number={1}, journal={Journal of the American Ceramic Society}, publisher={Wiley}, author={Samantaray, Malay M. and Gurav, Abhijit and Dickey, Elizabeth C. and Randall, Clive A.}, editor={Ching, W.-Y.Editor}, year={2011}, month={Aug}, pages={257–263} }
 @article{samantaray_gurav_dickey_randall_2011, title={Electrode Defects in Multilayer Capacitors Part II: Finite Element Analysis of Local Field Enhancement and Leakage Current in Three-Dimensional Microstructures}, volume={95}, ISSN={0002-7820}, url={http://dx.doi.org/10.1111/j.1551-2916.2011.04768.x}, DOI={10.1111/j.1551-2916.2011.04768.x}, abstractNote={Multilayer ceramic capacitors (MLCCs), owing to their processing conditions, can exhibit microstructure defects, such as electrode porosity and roughness. The effect of such extrinsic defects on the electrical performance of these devices needs to be understood to achieve successful miniaturization. To understand the influence of microstructural defects on field distributions and leakage current, the three-dimensional (3-D) microstructure of a local region in MLCCs is reconstructed using a serial-sectioning technique in the focused ion beam. This microstructure is then converted into a finite element model to simulate the perturbations in electric field due to the presence of electrode defects. The electric field is significantly enhanced in the vicinity of such defects, and this is expected to have a bearing on the leakage current density of these devices. To simulate the scaling effects, the dielectric layer thickness is reduced in the 3-D microstructure keeping the same electrode morphology. It is seen that the effect of microstructure defects is more pronounced as one approaches thinner layers, leading to higher local electric field concentrations and a concomitant drop in insulation resistance.}, number={1}, journal={Journal of the American Ceramic Society}, publisher={Wiley}, author={Samantaray, Malay M. and Gurav, Abhijit and Dickey, Elizabeth C. and Randall, Clive A.}, editor={Ching, W.-Y.Editor}, year={2011}, month={Aug}, pages={264–268} }
 @article{li_ko_trolier-mckinstry_dickey_2011, title={Energy Loss Near-Edge Fine Structure of Oxygen K of Spinel NixMn3-xO4}, volume={17}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927611004879}, DOI={10.1017/S1431927611004879}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.}, number={S2}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Li, J and Ko, S and Trolier-McKinstry, S and Dickey, E}, year={2011}, month={Jul}, pages={800–801} }
 @article{eichfeld_shen_eichfeld_mohney_dickey_redwing_2011, title={Gas phase equilibrium limitations on the vapor-liquid-solid growth of epitaxial silicon nanowires using SiCl(4)}, volume={26}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000296083100009&KeyUID=WOS:000296083100009}, DOI={10.1557/jmr.2011.144}, number={17}, journal={Journal of Materials Research}, author={Eichfeld, Sarah M. and Shen, Haoting and Eichfeld, Chad M. and Mohney, Suzanne E. and Dickey, Elizabeth C. and Redwing, Joan M.}, year={2011}, pages={2207–2214} }
 @article{saint john_shin_lee_ajmera_syllaios_dickey_jackson_podraza_2011, title={Influence of microstructure and composition on hydrogenated silicon thin film properties for uncooled microbolometer applications}, volume={110}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000293956600076&KeyUID=WOS:000293956600076}, DOI={10.1063/1.3610422}, abstractNote={Doped n- and p-type hydrogenated silicon (Si:H) thin films prepared by plasma enhanced chemical vapor deposition have been investigated for uncooled microbolometer applications. The material microstructure has been studied by in situ real time spectroscopic ellipsometry collected during thin film deposition or ex situ spectroscopic ellipsometry measurements on a static sample with a multiple sample analysis technique. The key electrical properties of interest, including film resistivity (ρ), temperature coefficient of resistance (TCR), and 1/f noise, have been measured as a function of deposition conditions for p-type amorphous hydrogenated silicon (a-Si:H) films and microcrystalline content for n-type amorphous (a), microcrystalline (µc), and mixed-phase amorphous + microcrystalline (a + µc) Si:H films. The TCR and 1/f noise values were compared for p- and n-type a-Si:H samples in the resistivity range of 100 < ρ < 3000 Ω cm and show that for a given resistivity, amorphous p-type films exhibit a lower 1/...}, number={3}, journal={Journal of Applied Physics}, author={Saint John, D. B. and Shin, H. -B. and Lee, M. -Y. and Ajmera, S. K. and Syllaios, A. J. and Dickey, E. C. and Jackson, T. N. and Podraza, N. J.}, year={2011} }
 @article{white_kunkle_polotai_dickey_2011, title={Microstructure and hardness scaling in laser-processed B(4)C-TiB(2) eutectic ceramics}, volume={31}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000290552400006&KeyUID=WOS:000290552400006}, DOI={10.1016/j.jeurceramsoc.2010.06.013}, abstractNote={Surface layers of the pseudo-binary eutectic comprised of boron carbide (B4C) and titanium diboride (TiB2) were directionally solidified via direct laser irradiation in an argon atmosphere. The resulting surface eutectic layers had highly oriented lamellar microstructures, whose scale (i.e. interlamellar spacing) was controlled directly by the laser scan rate, following an inverse square root dependence for lower solidification velocities. Higher velocities (>∼4.2 mm/s) departed from this relationship, although well-ordered microstructures were still achieved. A concomitant increase in the Vickers hardness with decreasing interlamellar spacing was observed, although the trend did not correspond to traditional Hall–Petch behavior. The hardness of the eutectic composites became load-independent at indenter loads greater than 9.81 N, indicating a potential transition from plastic to fractural deformation during indentation. A Vickers hardness of 32 GPa was achieved in the highest solidification velocity samples (42 mm/s) which had interlamellar spacings of 180 nm.}, number={7}, journal={Journal of the European Ceramic Society}, author={White, Ryan M. and Kunkle, Jamie M. and Polotai, Anton V. and Dickey, Elizabeth C.}, year={2011}, pages={1227–1232} }
 @article{gauntt_li_cabarcos_basantani_venkatasubramanian_bharadwaja_podraza_jackson_allara_antrazi_et al._2011, title={Microstructure of Vanadium Oxide Used in Microbolometers}, volume={8012}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000294735100128&KeyUID=WOS:000294735100128}, DOI={10.1117/12.884161}, abstractNote={Reactive pulsed DC sputtering was used to grow a systematic series of films with resistivity ranging from 1 × 10<sup>-3</sup> to 6.8 × 10<sup>4</sup> Ohm cm and TCR varying from 0 to -4% K-1. Throughout the parameter space studied a transition from amorphous to nano-crystalline growth was observed. Films in the resistivity range of interest for microbolometers contained a FCC VOx (0.8 < x < 1.3) phase. Altering the sputtering energetics via substrate biasing resulted in highlycolumnar, nano-twinned grains of FCC VO<sub>x</sub>, providing a microstructure reminiscent of ion beam sputtered bolometer material. Electron diffraction in the TEM confirmed the presence of a secondary, oxygen-rich amorphous phase. Micro- Raman spectroscopy, which was also found to be sensitive to the secondary amorphous phase, was used to probe the chemical composition and morphology of VO<sub>x</sub> thin films. Raman spectra from high resistivity amorphous films show a broad feature around ~890 cm<sup>-1</sup>, while spectra from lower resistivity nano-crystalline films exhibit this same amorphous feature and a second broad feature at ~320 cm<sup>-1</sup>. The resulting microstructure can be described as a nano-composite material composed of a low-resistivity crystalline phase embedded in a high-resistivity amorphous matrix. Our results suggest that both phases are required to achieve a high TCR, low resistivity material.}, number={ARTN 80123T}, journal={Infrared Technology and Applications Xxxvii}, author={Gauntt, BD and Li, J and Cabarcos, OM and Basantani, HA and Venkatasubramanian, C and Bharadwaja, SSN and Podraza, NJ and Jackson, TN and Allara, DL and Antrazi, S and et al.}, year={2011} }
 @inproceedings{ko_li_lee_dickey_jackson_trolier-mckinstry_2011, title={New Materials for Uncooled IR Imaging: Nickel Manganite Thin Films Grown by Spin Spray}, volume={8012}, url={https://app.dimensions.ai/details/publication/pub.1038864163}, DOI={10.1117/12.884636}, abstractNote={Ceramic thermistors like VOx, amorphous Si, and NiMn2O4 are used for thermal sensing applications such as microbolometers and infrared sensors. These materials should have large temperature coefficient of resistance (TCR), high sensitivity, and low noise for these applications. Nickel manganite films have large TCR (>-3%/K) and good environmental stability, so that the properties are robust during subsequent processing. To improve the ability to prepare manganite spinels on pre-existing circuitry, new techniques that enable low-temperature depositions need to be developed. To address this, the spin spray technique was adopted in this work; this approach is both low cost and permits low process temperatures (<100oC). Spin spray deposition is accomplished using two dilute water-based solutions: a reaction solution and oxidizing solution. The reaction solution consists of metal salts like nickel chloride and manganese chloride while the oxidizing solution contains pH buffer, pH adjuster, and oxidizing agent. To grow films, the solution was nebulized by a nitrogen carrier gas and sprayed onto a rotating silicon substrate with a 1μm thick SiO2 buffer layer. As-deposited nickel manganite films were identified as nanocrystalline spinel by TEM analysis. The TCR values of nickel manganite film and nickel copper manganite film were about -3.6 %/K and -2.9 %/K respectively. Adding Cu allowed the electric resistivity to be tuned to less than 1000 Ω-cm. The normalized Hooge parameter was around 1.7x10- 21 cm3.© (2011) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.}, number={ARTN 80123S}, booktitle={Proceedings of SPIE}, author={Ko, SW and Li, J and Lee, M-Y and Dickey, E and Jackson, T and Trolier-McKinstry, S}, year={2011} }
 @article{podraza_saint john_ko_schulze_li_dickey_trolier-mckinstry_2011, title={Optical and structural properties of solution deposited nickel manganite thin films}, volume={519}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000289174200077&KeyUID=WOS:000289174200077}, DOI={10.1016/j.tsf.2010.11.088}, abstractNote={Nickel manganite thin films of interest for microbolometer applications have been prepared using chemical solution and spin spray deposition and studied using transmission electron microscopy to quantify the material crystallinity and spectroscopic ellipsometry to extract the complex dielectric function (ε = ε 1 + iε 2 ) and film microstructure. A parameterization for ε over a spectral range from 0.04 to 5.15 eV has been developed to model well-crystallized nickel manganite, and the visible-range critical point features, infrared vibrations, and optical absorption onset have been identified. A multiple sample analysis structural model and procedure has been developed for spin spray deposited films exhibiting complicated void evolutions with thickness. Variations in ε and crystallite grain size have been observed as a function of film processing and indicate that the optical properties and microstructural information gained from spectroscopic ellipsometry is useful in process monitoring for this material system.}, number={9}, journal={Thin Solid Films}, author={Podraza, N. J. and Saint John, D. B. and Ko, S. W. and Schulze, H. M. and Li, J. and Dickey, E. C. and Trolier-McKinstry, S.}, year={2011}, pages={2919–2923} }
 @inproceedings{yoon_yuwen_shen_podraza_mallouk_dickey_redwing_wronski_mayer_2011, title={Parametric study of micropillar array solar cells}, url={https://app.dimensions.ai/details/publication/pub.1094834874}, DOI={10.1109/PVSC.2011.6185905}, abstractNote={Micro/nano pillar arrays are a promising architecture for high-efficiency solar cells that employ inexpensive photovoltaic materials with short minority carrier diffusion lengths (L n, p ). To investigate design tradeoffs of the radial junction array solar cells, we fabricated 25 μm tall c-Si pillar array devices having different diameters and pillar filling ratios. The high-aspect-ratio radial n+-p+ junctions were formed by gas phase diffusion of an n-type dopant into etched p-type Si pillars. The c-Si pillar arrays showed clear rectifying properties. The spectral reflectance decreased as the pillar filling ratio increased from 0.2 to 0.5, and no subsequent decrease was observed above a filling ratio of 0.5. Approximately two times higher cell efficiency was obtained with an 8 μm diameter ( n ) pillar array than with a 32 μm diameter (>3 L n ) pillar array having the same pillar filling ratio.}, booktitle={Conference Record IEEE Photovoltaic Specialists Conference}, author={Yoon, HP and Yuwen, YA and Shen, H and Podraza, NJ and Mallouk, TE and Dickey, EC and Redwing, JA and Wronski, CR and Mayer, TS}, year={2011}, month={Dec}, pages={000303–000306} }
 @article{ko_li_podraza_dickey_trolier-mckinstry_2011, title={Spin Spray-Deposited Nickel Manganite Thermistor Films For Microbolometer Applications}, volume={94}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000286830100038&KeyUID=WOS:000286830100038}, DOI={10.1111/j.1551-2916.2010.04097.x}, abstractNote={Nickel manganite thin films are good candidates for thermal imaging applications because of their large temperature coefficient of resistance (TCR), (>−3%/K) and good environmental stability. To enable low-temperature deposition (90°C) on preexisting circuitry, a spin spray technique was developed for these materials. As-deposited manganese oxide films show well-developed X-ray diffraction patterns, while as-deposited nickel manganite films exhibit a nanocrystalline spinel structure. Low-temperature (400°C) postdeposition annealing leads to densification of the nanocrystalline nickel manganite spinel films. Spectroscopic ellipsometry measurements on annealed films provide complex dielectric function spectra over a range from 0.75 to 5.15 eV with comparable features with those found in films prepared by a chemical solution method. Energy-dispersive X-ray spectroscopy indicates that the final composition of the films is Ni deficient relative to the starting solution composition. The TCR of the nickel manganite films annealed at 400°C in an argon atmosphere is −3.6%/K. Doping the nickel manganite films with zinc results in an improvement of crystallinity, but leads to substantial increases in the electrical resistivity. Copper doping reduces the resistivity of the films to <1.0 kΩ·cm without degrading the crystalline quality, thus resulting in films suitable for microbolometer applications.}, number={2}, journal={Journal of the American Ceramic Society}, author={Ko, Song Won and Li, Jing and Podraza, Nikolas J. and Dickey, Elizabeth C. and Trolier-McKinstry, Susan}, year={2011}, pages={516–523} }
 @article{white_dickey_2011, title={The Effects of Residual Stress Distributions on Indentation-induced Microcracking in B4C-TiB2 Eutectic Ceramic Composites}, volume={94}, ISSN={["0002-7820"]}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000297026700071&KeyUID=WOS:000297026700071}, DOI={10.1111/j.1551-2916.2011.04664.x}, abstractNote={The boron carbide (B4C) titanium diboride (TiB2) ceramic eutectic is being investigated for armor and tribological applications. Electron diffraction shows [110] TiB2//[211] B4C//growth direction, (0001) TiB2//(20) B4C is parallel to the interface plane, and transmission electron microscopy (TEM) imaging reveals no interface phase. Thermal residual stress distributions are calculated via finite element modeling of an experimental eutectic microstructure. The B4C matrix is found to be about 400 MPa in compression, and the TiB2 lamellae approximately 1.3 GPa in tension. Stress and strain energy concentrations are found at the tips of TiB2 lamellae. TEM of deformed materials correlates well with the finite element calculations, showing preferential fracture in areas of stress concentration. Interfacial delamination and crack deflection are also observed in deformed materials.}, number={11}, journal={JOURNAL OF THE AMERICAN CERAMIC SOCIETY}, author={White, Ryan M. and Dickey, Elizabeth C.}, year={2011}, month={Nov}, pages={4032–4039} }
 @article{saint john_shin_lee_dickey_podraza_jackson_2011, title={Thin Film Silicon and Germanium for Uncooled Microbolometer Applications}, volume={8012}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000294735100129&KeyUID=WOS:000294735100129}, DOI={10.1117/12.884269}, abstractNote={Hydrogenated silicon (Si:H) and germanium (Ge:H) are assessed for use as the resistive sensing layer in uncooled infrared microbolometer applications. N-type doped Si:H and undoped Ge:H thin films have been deposited using plasma enhanced chemical vapor deposition (PECVD) and monitored during growth using in situ, real time spectroscopic ellipsometry (RTSE) to track changes in the growth evolution and structure occurring within a single film as a function of thickness. Amorphous germanium (a-Ge) films prepared by sputtering and amorphous n-type doped silicon carbon alloy films (a-Si<sub>1-x</sub>Cx:H) films prepared by PECVD have also been studied by ex situ spectroscopic ellipsometry. Variations in the electrical properties of interest including film resistivity, temperature coefficient of resistance, and 1/f noise character in the form of the normalized Hooge parameter have been tracked as a function of the structure of the material as determined by deposition conditions and characterized by spectroscopic ellipsometry. Such notable variations observed include the effects of transitioning from amorphous to microcrystalline material in n-type Si:H; the addition of carbon to increase disorder in n-type a-Si:H; effects of process parameters for sputtered a-Ge; and a comparison of n-type a-Si:H, ntype a-Si<sub>1-x</sub>Cx:H, and undoped a-Ge:H properties for films all prepared by PECVD.}, number={ARTN 80123U}, journal={Infrared Technology and Applications Xxxvii}, author={Saint John, DB and Shin, H-B and Lee, M-Y and Dickey, EC and Podraza, NJ and Jackson, TN}, year={2011} }
 @article{sloppy_podraza_dickey_macdonald_2010, title={Complex dielectric functions of anodic bi-layer tantalum oxide}, volume={55}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000284443400056&KeyUID=WOS:000284443400056}, DOI={10.1016/j.electacta.2010.07.077}, abstractNote={Abstract The optical properties and structure of anodic oxides are dependent on the anodization conditions. For tantalum oxide formed in dilute phosphoric acid, the anodic oxide forms as two chemically distinct layers, referred to as a bi-layer, where the inner layer is pure tantalum oxide and the outer layer contains incorporated phosphate. The complex dielectric functions of the individual inner and outer layers are determined using spectroscopic ellipsometry. The dielectric functions of the bi-layers are compared to mono-layer oxides formed in sodium sulfate, and the effects of hydrothermal sealing are explored. For bi-layer oxides formed to 70 V in phosphoric acid, the inner layer band gap is 4.37 ± 0.02 eV and the outer layer band gap is 3.86 ± 0.06 eV. Thin anodic oxides (∼6–15 nm) are best described by a mono-layer oxide model and exhibit higher optical absorption with a band gap of 3.98 ± 0.08 eV. This study shows that spectroscopic ellipsometry is a valuable tool in assessing processing–property relationships of multi-layer anodic films.}, number={28}, journal={Electrochimica Acta}, author={Sloppy, JD and Podraza, NJ and Dickey, EC and Macdonald, DD}, year={2010}, pages={8751–8757} }
 @article{white_dickey_2010, title={Deformation Mechanisms and Residual Stress Distributions in B4C-TiB2 Directionally Solidified Eutectics}, volume={16}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927610060472}, DOI={10.1017/S1431927610060472}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.}, number={S2}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={White, R and Dickey, EC}, year={2010}, month={Jul}, pages={216–217} }
 @article{weng_burke_dickey_redwing_2010, title={Effect of reactor pressure on catalyst composition and growth of GaSb nanowires}, volume={312}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000274761900007&KeyUID=WOS:000274761900007}, DOI={10.1016/j.jcrysgro.2009.11.035}, abstractNote={Abstract Au-assisted metalorganic chemical vapor deposition was employed for the synthesis of GaSb nanowires. X-ray energy dispersive spectrometry indicates that the composition of catalyst particles depends on the reactor pressure at constant growth temperature and V/III ratio. The catalyst particles were ternary Au–Ga–Sb alloys for nanowires grown at 100 and 200 Torr, suggesting a vapor–liquid–solid (VLS) nanowire growth mechanism. At 300 Torr, the catalyst particles were pure Ga and the self-catalytic VLS mechanism was responsible for the growth of the GaSb nanowires. The diameter and growth rate of the nanowires, as well as the contact angle between the catalyst particle and the nanowire, were found to be dependent on the composition of the catalyst particles.}, number={4}, journal={Journal of Crystal Growth}, author={Weng, XJ and Burke, RA and Dickey, EC and Redwing, JM}, year={2010}, pages={514–519} }
 @article{sloppy_macdonald_dickey_2010, title={Growth Laws of Bilayer Anodized Tantalum Oxide Films Formed in Phosphoric Acid}, volume={157}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000276555300034&KeyUID=WOS:000276555300034}, DOI={10.1149/1.3327883}, number={5}, journal={Journal of the Electrochemical Society}, author={Sloppy, JD and Macdonald, DD and Dickey, EC}, year={2010}, pages={C157–C165} }
 @article{freeman_lessner_kramer_li_dickey_koenitzer_mann_chen_kinard_qazi_2010, title={Low Voltage Specific Charge (CV/g) Loss in Tantalum Capacitors}, volume={157}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000278182600059&KeyUID=WOS:000278182600059}, DOI={10.1149/1.3391671}, abstractNote={The systematic decrease in charge per unit weight in electrolytic tantalum capacitors as a function of decreasing anodization voltage is explored from both experimental and theoretical viewpoints for a range of tantalum particle sizes. Analysis by transmission electron microscopy shows that a native thermal oxide about 3.3 nm in thickness is present on the tantalum surface before anodization and that the thickness is independent of tantalum particle size. Studies in which the initial oxide thickness is altered via a preanodization heat-treatment show that the anodic oxide thickness becomes independent of the initial thermal oxide thickness once its thickness is exceeded. A theoretical model based on a cylindrical geometry explains the loss in the with decreasing anodization voltage and attributes the behavior to the 3.3 nm oxide thickness corresponding to zero anodization voltage.}, number={7}, journal={Journal of the Electrochemical Society}, author={Freeman, Y and Lessner, P and Kramer, AJ and Li, J and Dickey, EC and Koenitzer, J and Mann, L and Chen, Q and Kinard, T and Qazi, J}, year={2010}, pages={G161–G165} }
 @inproceedings{freeman_lessner_dickey_li_koenitzer_mann_chen_kinard_qazi_2010, title={Low voltage CV loss in tantalum capacitors}, booktitle={CARTS USA 2010}, author={Freeman, Y and Lessner, P and Dickey, E and Li, J and Koenitzer, J and Mann, L and Chen, Q and Kinard, T and Qazi, J}, year={2010}, month={Dec}, pages={77–88} }
 @inproceedings{podraza_saint john_li_wronski_dickey_collins_2010, title={MICROSTRUCTURAL EVOLUTION IN Si1-xGex:H THIN FILMS FOR PHOTOVOL TAlC APPLICATIONS}, url={https://app.dimensions.ai/details/publication/pub.1094432688}, DOI={10.1109/PVSC.2010.5616039}, abstractNote={The growth of hydrogenated silicon germanium alloy (Si 1−x Ge x :H) films by plasma enhanced chemical vapor deposition (PECVD) has been investigated using real time spectroscopic ellipsometry (RTSE) to understand the effect of incorporated Ge on the relationship between the evolution of microcrystallinity and the optical properties, the latter in the form of the complex dielectric function spectra (e = e 1 + ie 2 ). The motivation is to explore the variations in the growth and properties of microcrystalline alloy films that arise due to Ge incorporation in materials suitable for integration into thin film Si:H based photovoltaic devices. Variations in the microcrystal evolution and the optical properties of microcrystalline silicon germanium (μc-Si 1−x Ge x :H) are extracted from films that initially nucleate microcrystallites from the amorphous phase at a thickness near 100–200 A for alloy films spanning from Si:H to Ge:H. Although an increase in absorption is observed for the alloys, low Ge content films do not show the critical point features characteristic of crystalline Ge. Transmission electron micrographs (TEMs), the microstructural evolution obtained from RTSE, and a conical growth model for microcrystallites have been used to identify the average microcrystallite nucleation density and cone half angle. Monotonic decreases in the cone half angle with increasing Ge content are observed, indicating a reduced difference between the growth rates of the amorphous and microcrystalline phases with higher Ge incorporation. Also the nucleation density is lower in the alloy films with higher incorporation of Ge, which is consistent with a weaker tendency for microcrystallite formation expected on a more disordered alloy substrate.}, booktitle={Conference Record IEEE Photovoltaic Specialists Conference}, author={Podraza, NJ and Saint John, DB and Li, J and Wronski, CR and Dickey, EC and Collins, RW}, year={2010} }
 @article{podraza_saint john_li_wronski_dickey_collins_ieee_2010, title={MICROSTRUCTURAL EVOLUTION IN Si1-xGex:H THIN FILMS FOR PHOTOVOL TAlC APPLICATIONS}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000287579500033&KeyUID=WOS:000287579500033}, journal={35th Ieee Photovoltaic Specialists Conference}, author={Podraza, Nikolas J. and Saint John, David B. and Li, Jing and Wronski, Christopher R. and Dickey, Elizabeth C. and Collins, Robert W. and IEEE}, year={2010}, pages={158–163} }
 @article{li_gauntt_podraza_jackson_dickey_2010, title={Micro-Twinned VOx Nanocrystalline Film and Hopping Conduction}, volume={16}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927610060708}, DOI={10.1017/S1431927610060708}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.}, number={S2}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Li, J and Gauntt, BD and Podraza, NJ and Jackson, TN and Dickey, EC}, year={2010}, month={Jul}, pages={1274–1275} }
 @article{li_gauntt_dickey_2010, title={Microtwinning in highly nonstoichiometric VOx thin films}, volume={58}, ISSN={1359-6454}, url={http://dx.doi.org/10.1016/j.actamat.2010.05.035}, DOI={10.1016/j.actamat.2010.05.035}, abstractNote={Both pulsed-DC biased and commercial ion-beam sputtered VOx thin films maintain a face-centered-cubic nanocrystalline phase, even for stoichiometries of x > 1.5, which is well outside the bulk equilibrium solubility range for cubic VOx. Many of these highly nonstoichiometric films exhibit a high density of microtwins, which give rise to unusual fine structure in the selected-area electron diffraction patterns, namely: an additional defect ring; a significant broadening of the {2 0 0} ring; pairs of parallel rod features which are tangent to the additional defect ring; and additional fine-structure features between the {2 0 0} and {2 2 0} rings. The formation of the microtwins is correlated with the coalescence of vanadium vacancies along the {1 1 1} twin planes in the crystalline lattice.}, number={15}, journal={Acta Materialia}, publisher={Elsevier BV}, author={Li, Jing and Gauntt, Bryan D. and Dickey, Elizabeth C.}, year={2010}, month={Sep}, pages={5009–5014} }
 @inproceedings{bharadwaja_venkatasubramanyam_fieldhouse_gauntt_lee_ashok_dickey_jackson_horn_2010, title={PROCESSING ISSUES IN PULSE DC SPUTTERING OF VANADIUM OXIDE THIN FILMS FOR UNCOOLED INFRARED DETECTORS}, volume={221}, url={https://app.dimensions.ai/details/publication/pub.1016396477}, DOI={10.1002/9780470930915.ch16}, abstractNote={This chapter contains sections titled: Introduction Pulsed-DC Sputtered Vox Thin Films Electrical Properties Of Vox Thin Films Results and Discussion Summary}, booktitle={Ceramic Transactions}, author={Bharadwaja, SSN and Venkatasubramanyam, C and Fieldhouse, N and Gauntt, B and Lee, MY and Ashok, S and Dickey, EC and Jackson, TN and Horn, M}, year={2010}, pages={177-+} }
 @article{bharadwaja_venkatasubramanyam_fieldhouse_gauntt_lee_ashok_dickey_jackson_horn_nair_et al._2010, title={PROCESSING ISSUES IN PULSE DC SPUTTERING OF VANADIUM OXIDE THIN FILMS FOR UNCOOLED INFRARED DETECTORS}, volume={221}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000287221600016&KeyUID=WOS:000287221600016}, journal={Advances in Electroceramic Materials Ii}, author={Bharadwaja, S. S. N. and Venkatasubramanyam, C. and Fieldhouse, N. and Gauntt, B. and Lee, Myung Yoon and Ashok, S. and Dickey, E. C. and Jackson, T. N. and Horn, M. and Nair, KM and et al.}, year={2010}, pages={177–185} }
 @article{kendrick_yoon_yuwen_barber_shen_mallouk_dickey_mayer_redwing_2010, title={Radial junction silicon wire array solar cells fabricated by gold-catalyzed vapor-liquid-solid growth}, volume={97}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000282765700060&KeyUID=WOS:000282765700060}, DOI={10.1063/1.3496044}, abstractNote={The fabrication of radial junction silicon (Si) solar cells using Si wire arrays grown by Au-catalyzed vapor-liquid-solid growth on patterned Si substrates was demonstrated. An important step in the fabrication process is the repeated thermal oxidation and oxide etching of the Si wire arrays. The oxidation cleaning process removes residual catalyst material from the wire tips and exposes additional Au embedded in the material. Using this cleaning process and junction formation through POCl3 thermal diffusion, rectifying p-n junctions were obtained that exhibited an efficiency of 2.3% and open circuit voltages up to 0.5 V under Air Mass 1.5G illumination.}, number={14}, journal={Applied Physics Letters}, author={Kendrick, CE and Yoon, HP and Yuwen, YA and Barber, GD and Shen, HT and Mallouk, TE and Dickey, EC and Mayer, TS and Redwing, JM}, year={2010} }
 @article{weng_tian_schlom_dickey_2010, title={Structure and chemistry of the (111)Sc2O3/(0001) GaN epitaxial interface}, volume={96}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000278911500015&KeyUID=WOS:000278911500015}, DOI={10.1063/1.3454924}, abstractNote={The structure and chemistry of the (111)Sc2O3/(0001) GaN epitaxial interface grown by molecular-beam epitaxy have been investigated. High-resolution transmission electron microscopy reveals an abrupt Sc2O3/GaN interface with a hexagonal misfit dislocation network. These dislocations have Burgers vectors of (a/3)⟨112¯0⟩GaN and line directions parallel to ⟨11¯00⟩GaN⁠, with an average spacing of ∼3.8 nm⁠. Scanning transmission electron microscopy and electron energy loss spectrometry reveal the intermixing of Sc, O, and N over a region with a width of ∼1.5 nm at the interface.}, number={24}, journal={Applied Physics Letters}, author={Weng, X and Tian, W and Schlom, DG and Dickey, EC}, year={2010} }
 @article{gauntt_dickey_2010, title={The Effects of Nano-Crystal Distribution and Structure on the Transport in Vanadium Oxide Thin Films}, volume={16}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927610060721}, DOI={10.1017/S1431927610060721}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2010 in Portland, Oregon, USA, August 1 – August 5, 2010.}, number={S2}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Gauntt, BD and Dickey, EC}, year={2010}, month={Jul}, pages={1654–1655} }
 @article{podraza_li_wronski_dickey_collins_2009, title={Analysis of controlled mixed-phase, amorphous plus microcrystalline. silicon thin films by real time spectroscopic ellipsometry}, volume={27}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000271284500001&KeyUID=WOS:000271284500001}, DOI={10.1116/1.3212893}, abstractNote={Engineered thin films consisting of periodic arrays of silicon microcrystallites in a hydrogenated amorphous silicon host matrix have been prepared by plasma-enhanced chemical vapor deposition where the hydrogen dilution of silane is modulated in multiple cycles. These types of films have been guided by a phase evolution diagram, depicting the deposition conditions and film thickness at which the material exhibits amorphous, microcrystalline, or mixed-phase (amorphous+microcrystalline) characteristics, developed for intrinsic Si:H prepared with varying H2 dilution on unhydrogenated a-Si:H. Real time spectroscopic ellipsometry (RTSE) has been used in situ to noninvasively determine the phase evolution of the resulting hydrogenated mixed-phase (amorphous+microcrystalline) silicon thin films and corroborated with dark-field transmission electron microscopy. Such tailored microstructures are of growing interest as components of thin film photovoltaic devices, and RTSE is shown to be a key technique for structure verification.}, number={6}, journal={Journal of Vacuum Science & Technology a}, author={Podraza, NJ and Li, J and Wronski, CR and Dickey, EC and Collins, RW}, year={2009}, pages={1255–1259} }
 @article{polotai_jeong_yang_dickey_randall_pinceloup_gurav_2009, title={Effect of Cr additions on the electrical properties of Ni-BaTiO3 ultra-thin multilayer capacitors}, volume={23}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000268772500002&KeyUID=WOS:000268772500002}, DOI={10.1007/s10832-008-9496-0}, number={1}, journal={Journal of Electroceramics}, author={Polotai, AV and Jeong, TH and Yang, GY and Dickey, EC and Randall, CA and Pinceloup, P and Gurav, AS}, year={2009}, pages={6–12} }
 @article{li_finnis_he_behera_phillpot_sinnott_dickey_2009, title={Energetics of charged point defects in rutile TiO2 by density functional theory}, volume={57}, ISSN={1359-6454}, url={http://dx.doi.org/10.1016/j.actamat.2009.08.014}, DOI={10.1016/j.actamat.2009.08.014}, abstractNote={The defect formation energies of all possible charge states of point defects in TiO2, including titanium interstitials, titanium vacancies and oxygen vacancies, are calculated in the phase space of temperature, oxygen partial pressure and Fermi level by combining density functional theory (DFT) and thermodynamic calculations. The point defect phase diagram illustrates that fully charged defects dominate in most regimes. The calculations not only give reasonable defect formation energies compared with prior experimental measurements, but also predict n-type TiO2 at high T and low PO2, and p-type TiO2 at low T and high PO2, which agrees well with experimental data. In addition, we evaluate methods for correcting the effects of artificial electrostatic interactions caused by periodic boundary conditions in the DFT calculations, including the electrostatic potential alignment correction (ΔV correction) and the Makov–Payne correction.}, number={19}, journal={Acta Materialia}, publisher={Elsevier BV}, author={Li, X. and Finnis, M.W. and He, J. and Behera, R.K. and Phillpot, S.R. and Sinnott, S.B. and Dickey, E.C.}, year={2009}, month={Nov}, pages={5882–5891} }
 @article{redwing_nimmatoori_lew_zhang_zhang_clark_pan_dickey_swihart_barreca_et al._2009, title={Growth Mechanisms and Size-Dependent Characteristics of Si and Si1-xGex Nanowires}, volume={25}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000338305900149&KeyUID=WOS:000338305900149}, DOI={10.1149/1.3207718}, number={8}, journal={Eurocvd 17 / Cvd 17}, author={Redwing, J. M. and Nimmatoori, P. and Lew, K. K. and Zhang, X. and Zhang, Q. and Clark, T. E. and Pan, L. and Dickey, E. C. and Swihart, MT and Barreca, D and et al.}, year={2009}, pages={1145–1152} }
 @article{cooley_clark_liu_eichfeld_dickey_mohney_crooker_samarth_2009, title={Growth of Magneto-optically Active (Zn,Mn)Se Nanowires}, volume={9}, ISSN={1530-6984 1530-6992}, url={http://dx.doi.org/10.1021/nl901272q}, DOI={10.1021/nl901272q}, abstractNote={We describe the growth of Zn1−xMnxSe nanowires in ultrahigh vacuum seeded by Au nanodroplets. Electron microscopy reveals the formation of single-crystal c-axis wurtzite nanowires (typically 1−3 μm long) with Mn concentrations up to x ≈ 0.6, accompanied by a dense horizontal undergrowth of shorter, crooked nanowires. Magnetophotoluminescence measurements show evidence for sp−d exchange effects in a reduced symmetry environment. We find that the optical emission is surprisingly dominated by the undergrowth of crooked nanowires.}, number={9}, journal={Nano Letters}, publisher={American Chemical Society (ACS)}, author={Cooley, B. J. and Clark, T. E. and Liu, B. Z. and Eichfeld, C. M. and Dickey, E. C. and Mohney, S. E. and Crooker, S. A. and Samarth, N.}, year={2009}, month={Sep}, pages={3142–3146} }
 @article{lee_kupp_stevenson_anderson_messing_li_dickey_dumm_simonaitis-castillo_quarles_2009, title={Hot Isostatic Pressing of Transparent Nd:YAG Ceramics}, volume={92}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000267426500015&KeyUID=WOS:000267426500015}, DOI={10.1111/j.1551-2916.2009.03029.x}, abstractNote={This paper demonstrates that fine-grained (2–3 μm), transparent Nd:YAG can be achieved at SiO2 doping levels as low as 0.02 wt% by the sinter plus hot isostatic pressing (HIP) approach. Fine grain size is assured by sintering to 98% density, in order to limit grain growth, followed by HIP. Unlike dry-pressed samples, tape-cast samples were free of large, agglomerate-related pores after sintering, and thus high transparency (i.e., >80% transmission at 1064 nm) could be achieved by HIP at <1750°C along with lower silica levels, thereby avoiding conditions shown to cause exaggerated grain growth. Grain growth was substantially limited at lower SiO2 levels because silica is soluble in the YAG lattice up to ∼0.02–0.1 wt% at 1750°C, thus allowing sintering and grain growth to occur by solid-state diffusional processes. In contrast, liquid phase enhanced densification and grain growth occur at ∼0.08–0.14 wt% SiO2, especially at higher temperatures, because the SiO2 solubility limit is exceeded.}, number={7}, journal={Journal of the American Ceramic Society}, author={Lee, SH and Kupp, ER and Stevenson, AJ and Anderson, JM and Messing, GL and Li, X and Dickey, EC and Dumm, JQ and Simonaitis-Castillo, VK and Quarles, GJ}, year={2009}, pages={1456–1463} }
 @article{gauntt_dickey_2009, title={In-situ TEM study of thin-film vanadium oxide stability}, volume={15}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000208119100495&KeyUID=WOS:000208119100495}, DOI={10.1017/S1431927609096366}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009}, journal={Microscopy and Microanalysis}, author={Gauntt, B. D. and Dickey, E. C.}, year={2009}, pages={1002–1003} }
 @article{gauntt_dickey_horn_2009, title={Stoichiometry and microstructural effects on electrical conduction in pulsed dc sputtered vanadium oxide thin films}, volume={24}, ISSN={0884-2914 2044-5326}, url={http://dx.doi.org/10.1557/JMR.2009.0183}, DOI={10.1557/JMR.2009.0183}, number={4}, journal={Journal of Materials Research}, publisher={Cambridge University Press (CUP)}, author={Gauntt, Bryan D. and Dickey, Elizabeth C. and Horn, Mark W.}, year={2009}, month={Apr}, pages={1590–1599} }
 @article{li_gauntt_kulik_dickey_2009, title={Stoichiometry of Nanocrystalline VOx Thin Films Determined by Electron Energy Loss Spectroscopy}, volume={15}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000208119100496&KeyUID=WOS:000208119100496}, DOI={10.1017/S1431927609092770}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2009 in Richmond, Virginia, USA, July 26 – July 30, 2009}, journal={Microscopy and Microanalysis}, author={Li, J. and Gauntt, B. D. and Kulik, J. and Dickey, E. C.}, year={2009}, pages={1004–1005} }
 @article{nimmatoori_zhang_dickey_redwing_2009, title={Suppression of the vapor-liquid-solid growth of silicon nanowires by antimony addition}, volume={20}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000261647500014&KeyUID=WOS:000261647500014}, DOI={10.1088/0957-4484/20/2/025607}, abstractNote={The effect of Sb addition on the growth rate and structural properties of Si nanowires synthesized by vapor-liquid-solid growth was investigated. The nanowire growth rate was reduced by an order of magnitude following the addition of a low concentration pulse of trimethylantimony (TMSb) to the gas phase during growth. Transmission electron microscopy analysis revealed that the wires had a thick amorphous coating ( approximately 8 nm) around the catalyst particle and a distorted catalyst shape. Energy-dispersive x-ray spectroscopy showed the presence of trace amounts of Sb in the amorphous coating around the catalyst and at the catalyst-wire interface. Antimony was also found to be incorporated in the Si nanowires with a peak in the Sb concentration measured at the initial point where the TMSb pulse was added to the gas stream. The significant reduction in wire growth rate was attributed to Sb segregation at the vapor-liquid and liquid-solid interfaces which results in a change in interfacial energies and a reduction in the rate of Si incorporation at these interfaces.}, number={2}, journal={Nanotechnology}, author={Nimmatoori, P and Zhang, Q and Dickey, EC and Redwing, JM}, year={2009} }
 @article{schulze_li_dickey_trolier-mckinstry_2009, title={Synthesis, Phase Characterization, and Properties of Chemical Solution-Deposited Nickel Manganite Thermistor Thin Films}, volume={92}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000264241200027&KeyUID=WOS:000264241200027}, DOI={10.1111/j.1551-2916.2009.02944.x}, abstractNote={Nickel manganite spinel thin films prepared by chemical solution deposition exhibit negative temperature coefficient of resistance (TCR) values between −3.3 and −4.5%/K. In contrast to bulk thermistors, dense films could be prepared completely within the spinel phase field. Thus, decomposition into the NiO phase and a Mn-rich spinel, which is problematic in bulk ceramics, is minimized in thin films. For films prepared outside of the single-phase field, phase separation cannot always be detected using X-ray diffraction. In such cases, transmission electron microscopy is useful in identifying decomposition. It is found that the lattice parameters for films with compositions ranging between Mn/(Mn+Ni)=0.14 and 0.77 are smaller than the values reported for nickel manganite spinels, suggesting cation deficiency. Single-phase spinel films are compared with single-phase bixbyite films synthesized between 630° and 930°C. The bixbyite phase exhibits lower TCR and lower resistivity (TCR=−3.1 to −3.3%/K and resistivity values=400–1600 Ω·cm) compared with spinel (TCR=−3.6 to −4.1%/K and resistivity values=3500–21 000 Ω·cm). Composite films (achieved by controlling the pyrolysis to create a low local pO2 during annealing) show intermediate values (TCR=−3.0 to −3.8%/K and resistivity values=470–6600 Ω·cm).}, number={3}, journal={Journal of the American Ceramic Society}, author={Schulze, H and Li, J and Dickey, EC and Trolier-McKinstry, S}, year={2009}, pages={738–744} }
 @inproceedings{nimmatoori_zhang_zhang_dickey_redwing_2008, title={23b. Growth characteristics and properties of Si and Si <inf>1-x</inf>Ge<inf>x</inf> nanowires}, booktitle={AIChE Annual Meeting, Conference Proceedings}, author={Nimmatoori, P and Zhang, Q and Zhang, X and Dickey, EC and Redwing, JM}, year={2008}, month={Nov} }
 @inproceedings{nimmatoori_zhang_zhang_dickey_redwing_2008, title={23b. Growth characteristics and properties of Si and Si<inf>1-x</inf>Ge<inf>x</inf> nanowires}, booktitle={Nanoscale Science and Engineering Forum Conference, Presentations at the 2008 AIChE Spring National Meeting}, author={Nimmatoori, P and Zhang, Q and Zhang, X and Dickey, EC and Redwing, JM}, year={2008}, month={Jan}, pages={26–32} }
 @inproceedings{podraza_li_wronski_horn_dickey_collins_2008, title={Analysis of Compositionally and Structurally Graded Si:H and Si1-xGex:H Thin Films by Real Time Spectroscopic Ellipsometry}, volume={1066}, url={https://app.dimensions.ai/details/publication/pub.1067906026}, DOI={10.1557/PROC-1066-A10-01}, booktitle={MRS Online Proceedings Library}, author={Podraza, NJ and Li, J and Wronski, CR and Horn, MW and Dickey, EC and Collins, RW}, year={2008}, pages={253-+} }
 @inbook{podraza_li_wronski_horn_dickey_collins_2008, title={Analysis of Compositionally and Structurally Graded Si:H and Si1-xGex:H Thin Films by Real Time Spectroscopic Ellipsometry}, volume={1066}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000261398700036&KeyUID=WOS:000261398700036}, booktitle={Amorphous and Polycrystalline Thin-Film Silicon Science and Technology-2008}, author={Podraza, NJ and Li, J and Wronski, CR and Horn, MW and Dickey, EC and Collins, RW}, year={2008}, pages={253–258} }
 @article{podraza_li_wronski_dickey_horn_collins_2008, title={Analysis of Si1-xGex : H thin films with graded composition and structure by real time spectroscopic ellipsometry}, volume={205}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000255702600041&KeyUID=WOS:000255702600041}, DOI={10.1002/pssa.200777876}, abstractNote={Silicon-germanium (Si1−x Gex:H) thin films have been prepared by plasma enhanced chemical vapor deposition of SiH4 and GeH4 and measured during growth using real time spectroscopic ellipsometry. A two-layer virtual interface analysis has been applied to study the structural evolution of Si1−x Gex:H films that initially nucleate in the amorphous (a) phase, but evolve to the microcrystalline (μc) phase with accumulated thickness. The compositional evolution of alloy-graded a-Si1−x Gex:H has been studied as well using similar methods. Both types of films are of interest for Si-based photovoltaic devices. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)}, number={4}, journal={Physica Status Solidi a-Applications and Materials Science}, author={Podraza, NJ and Li, J and Wronski, CR and Dickey, EC and Horn, MW and Collins, RW}, year={2008}, pages={892–895} }
 @article{sloppy_li_dickey_2008, title={Anodic Tantalum Pentoxide: Chemical and Structural Characterization of a Bi-Layer Oxide}, volume={14}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S143192760808392X}, DOI={10.1017/S143192760808392X}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 – August 7, 2008}, number={S2}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Sloppy, J Ray and Li, J and Dickey, EC}, year={2008}, month={Aug}, pages={328–329} }
 @inproceedings{randall_polotai_yang_dickey_2008, title={Ceramic-electrode interfaces in cofired electroceramic multilayer components}, booktitle={A Global Road Map for Ceramic Materials and Technologies: Forecasting the Future of Ceramics, International Ceramic Federation - 2nd International Congress on Ceramics, ICC 2008, Final Programme}, author={Randall, CA and Polotai, AV and Yang, GY and Dickey, EC}, year={2008}, month={Dec} }
 @article{clark_nimmatoori_lew_pan_redwing_dickey_2008, title={Diameter Dependent Growth Rate and Interfacial Abruptness in Vapor–Liquid–Solid Si/Si1−xGex Heterostructure Nanowires}, volume={8}, ISSN={1530-6984 1530-6992}, url={http://dx.doi.org/10.1021/nl072849k}, DOI={10.1021/nl072849k}, abstractNote={A strong diameter dependence is observed in the interfacial abruptness and growth rates in Si/Si1−xGex axial heterostructure nanowires grown via Au-mediated low pressure CVD using silane and germane precursors. The growth of these nanowires has similarities to that of heterostructure thin films with similar compositional interfacial broadening, which increases with and is on the order with diameter. This broadening may reveal a fundamental challenge to fabrication of abrupt heterostructures via VLS growth.}, number={4}, journal={Nano Letters}, publisher={American Chemical Society (ACS)}, author={Clark, Trevor E. and Nimmatoori, Pramod and Lew, Kok-Keong and Pan, Ling and Redwing, Joan M. and Dickey, Elizabeth C.}, year={2008}, month={Apr}, pages={1246–1252} }
 @article{gauntt_li_kulik_dickey_2008, title={Disordered Vanadium Oxide Thin Films for Use in Infrared Detection}, volume={14}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927608086650}, DOI={10.1017/S1431927608086650}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 – August 7, 2008}, number={S2}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Gauntt, BD and Li, J and Kulik, J and Dickey, EC}, year={2008}, month={Aug}, pages={236–237} }
 @article{li_stevenson_messing_dickey_2008, title={EDX Analysis of Grain Boundary Segregation in 1 at% Nd Doped Polycrystalline YAG}, volume={14}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927608084134}, DOI={10.1017/S1431927608084134}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 – August 7, 2008}, number={S2}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Li, X and Stevenson, A and Messing, G and Dickey, EC}, year={2008}, month={Aug}, pages={1420–1421} }
 @article{polotai_fujii_shay_yang_dickey_randall_2008, title={Effect of Heating Rates during Sintering on the Electrical Properties of Ultra-Thin NiBaTiO3 Multilayer Ceramic Capacitors}, volume={91}, ISSN={0002-7820 1551-2916}, url={http://dx.doi.org/10.1111/j.1551-2916.2008.02517.x}, DOI={10.1111/j.1551-2916.2008.02517.x}, abstractNote={Microstructural control in thin-layer multilayer ceramic capacitors (MLCCs) is one of the present day challenges for increasing capacitive volumetric efficiency and high voltage dielectric properties. The present paper continues a series of investigations aimed at engineering the stability of ultra-thin Ni layers in base-metal electrode MLCCs. A kinetic approach based on the control of sintering profiles is found to not only prevent Ni electrode discontinuities, but also to significantly improve the interfacial electrical properties. Increasing sintering heating rates from 200 to 3000°C/h leads to a decrease in its temperature dependence of capacitance. Faster heating rates also reduce the BaTiO3 grain size, which is beneficial to the reliability of multilayer capacitors. A direct correlation between heating rates, the thickness of an interfacial (Ni, Ba, and Ti) alloy reaction layer and the interfacial contact resistance has been observed. The decrease in the alloy layer thickness at high heating rates leads to an increased effective Schottky barrier height between the dielectric and electrode toward its theoretical value of 1.25 eV for pure Ni–BaTiO3 interfaces.}, number={8}, journal={Journal of the American Ceramic Society}, publisher={Wiley}, author={Polotai, Anton V. and Fujii, Ichiro and Shay, Dennis P. and Yang, Gai-Ying and Dickey, Elizabeth C. and Randall, Clive A.}, year={2008}, month={Jun}, pages={2540–2544} }
 @article{acord_weng_dickey_snyder_redwing_2008, title={Effects of a compositionally graded buffer layer on stress evolution during GaN and AlxGa1-xN MOCVD on SiC substrates}, volume={310}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000255843200185&KeyUID=WOS:000255843200185}, DOI={10.1016/j.jcrysgro.2007.11.153}, abstractNote={In situ substrate curvature measurements were used to monitor stress evolution during metal organic chemical vapor deposition (MOCVD) of AlxGa1−xN epilayers (x=0, 0.5, 0.7) on 6H-SiC (0 0 0 1) substrates that were grown using compositionally graded AlN to AlxGa1−xN buffer layers. The results were compared to identical growths carried out using thin (∼80 nm) AlN buffer layers in order to assess the impact of the graded layer on the mean film stress and structural properties of AlxGa1−xN. Compositionally graded (AlN–GaN) layers effectively increased the mean compressive stress in GaN epilayers grown on SiC compared to samples grown on AlN buffer layers, with the mean stress in the GaN layer increasing with buffer layer thickness. Increasing buffer thickness correlated with a decrease in the threading dislocation density measured by plan-view-TEM. In contrast, the mean stress in high Al-fraction AlxGa1−xN epilayers (x=0.5 and 0.7) was not significantly altered by the use of AlN to AlxGa1−xN graded buffer layers and in some cases, the graded layer leads to a decrease in mean compressive stress in the films. The differences in stress evolution are explained in terms of the available compressive strain energy, which is suggested to be responsible for dislocation bending observed in the GaN graded layer samples.}, number={7-9}, journal={Journal of Crystal Growth}, author={Acord, JD and Weng, XJ and Dickey, EC and Snyder, DW and Redwing, JM}, year={2008}, pages={2314–2319} }
 @article{trammell_zhang_li_chen_dickey_2008, title={Equilibrium strain-energy analysis of coherently strained core-shell nanowires}, volume={310}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000257006800024&KeyUID=WOS:000257006800024}, DOI={10.1016/j.jcrysgro.2008.02.037}, abstractNote={In order to continue the performance enhancement of Si-based semiconductor devices, the number of devices on a chip as well as the performance of those devices must continue to improve. One method for improving device functionality is the incorporation of strained Si–Ge heterostructures. While such heterostructures have been the focus of much research in planar Si processing, only recently has the fabrication of such heterostructures in nanoscale semiconductors been addressed. In particular, the fabrication of a Si–Ge radial nanowire heterostructure requires a consideration of the epitaxial stability of the shell on the underlying core nanowire. This work develops a model for the strain state of a radial nanowire heterostructure, focusing on the particular example of Si–Ge. The behavior of the radial nanowire heterostructure is compared to that of a planar heterostructure, and we find that much higher strains can be achieved in the nanowire geometry.}, number={12}, journal={Journal of Crystal Growth}, author={Trammell, TE and Zhang, X and Li, YL and Chen, LQ and Dickey, EC}, year={2008}, pages={3084–3092} }
 @article{olszta_dickey_2008, title={Interface Stoichiometry and Structure in Anodic Niobium Pentoxide}, volume={14}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927608080756}, DOI={10.1017/S1431927608080756}, abstractNote={Abstract High-resolution transmission electron microscopy and electron energy loss spectroscopy (EELS) were performed on electrochemically anodized niobium and niobium oxide. Sintered anodes of Nb and NbO powders were anodized in 0.1 wt% H 3 PO 4 at 10, 20, and 65 V to form surface Nb 2 O 5 layers with an average anodization constant of 3.6 ± 0.2 nm/V. The anode/dielectric interfaces were continuous and the dielectric layers were amorphous except for occurrences of plate-like, orthorhombic pentoxide crystallites in both anodes formed at 65 V. Using EELS stoichiometry quantification and relative chemical shifts of the Nb M 4,5 ionization edge, a suboxide transition layer at the amorphous pentoxide interface on the order of 5 nm was detected in the Nb anodes, whereas no interfacial suboxide layers were detected in the NbO anodes.}, number={5}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Olszta, Matthew J. and Dickey, Elizabeth C.}, year={2008}, month={Sep}, pages={451–458} }
 @article{polotai_foreman_dickey_meinert_2008, title={Laser Surface Processing of B4C-TiB2 Eutectic}, volume={5}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000260544200009&KeyUID=WOS:000260544200009}, DOI={10.1111/j.1744-7402.2008.02229.x}, abstractNote={The formation of a directionally solidified non-oxide eutectic surface layer based on the 75 mol% B4C and 25 mol% TiB2 eutectic composition has been developed using a continuous-wave, high-power, CO2 laser. To prevent the oxidation of nonoxide compounds and to reduce thermal stress formation, an atmospherically controlled furnace capable of back-heating samples up to 1100°C during the laser processing has been employed. The effect of the laser scan rate on the eutectic microstructure formation is investigated. It is found that at relatively slow laser scan rates, ∼2–4 mm/s, the formation of a colony-type eutectic microstructure with submicrometer scale features is observed. At higher heating rates up to 42 mm/s, disordered eutectic grains with nanometer-scale TiB2 lamellae form. The dependence of the TiB2 interlamellar spacing on the crystallization rate in the laser solidified B4C–TiB2 eutectic has the same general trend as in the eutectic produced by a floating zone method. However, this method allows the production of much smaller microstructural length scales, on the order of 100 nm, as a consequence of the high crystallization velocity.}, number={6}, journal={International Journal of Applied Ceramic Technology}, author={Polotai, AV and Foreman, JF and Dickey, EC and Meinert, K}, year={2008}, pages={610–617} }
 @article{dickey_philips_polotai_2008, title={Microstructural and Interface Analysis of Ceramic Eutectic Composites}, volume={14}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927608088119}, DOI={10.1017/S1431927608088119}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 – August 7, 2008}, number={S2}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Dickey, EC and Philips, C and Polotai, AV}, year={2008}, month={Aug}, pages={142–143} }
 @article{john_podraza_gauntt_li_dickey_2008, title={Microstructural and Radial Distribution Function Analysis of Hydrogenated Silicon, Germanium, and Silicon-Germanium Alloy Thin Films}, volume={14}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927608087631}, DOI={10.1017/S1431927608087631}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 – August 7, 2008}, number={S2}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={John, DB Saint and Podraza, NJ and Gauntt, BD and Li, J and Dickey, EC}, year={2008}, month={Aug}, pages={406–407} }
 @article{lu_adu_gutierrez_chen_lew_nimmatoori_zhang_dickey_redwing_eklund_2008, title={Raman scattering from Si1-xGex alloy nanowires}, volume={112}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000253512400011&KeyUID=WOS:000253512400011}, DOI={10.1021/jp074764d}, abstractNote={We present Raman scattering results on crystalline Si1-xGex nanowires (0 < x < 1) grown by the vapor−liquid−solid growth mechanism using chemical vapor deposition. Typical nanowire diameters and lengths were in the range 80−110 nm and 15−40 μm, respectively. Three strong Raman bands were observed and identified as perturbed Si−Si (∼500 cm-1) modes, perturbed Ge−Ge (∼280 cm-1) modes, and intermediate frequency (∼400 cm-1) modes assigned to Si−Ge clusters. A broad band is observed in the range ∼75−110 cm-1 that is assigned to transverse acoustic modes. The compositional dependence of these Raman bands is similar to what is observed in bulk material and is also found to be in very good agreement with the recently calculated vibrational density of states for Si1-xGex nanoparticles.}, number={9}, journal={Journal of Physical Chemistry C}, author={Lu, QJ and Adu, KW and Gutierrez, HR and Chen, GG and Lew, KK and Nimmatoori, P and Zhang, X and Dickey, EC and Redwing, JM and Eklund, PC}, year={2008}, pages={3209–3215} }
 @inbook{polotai_cheng_agrawal_dickey_cytron_2008, title={SYNTHESIS OF CERAMIC EUTECTICS USING MICROWAVE PROCESSING}, volume={28}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000284980300011&KeyUID=WOS:000284980300011}, booktitle={Advances in Ceramic Armor Iii}, author={Polotai, AV and Cheng, JP and Agrawal, DK and Dickey, EC and Cytron, S}, year={2008}, pages={127–133} }
 @inproceedings{polotai_cheng_agrawal_dickey_cytron_2008, title={SYNTHESIS OF CERAMIC EUTECTICS USING MICROWAVE PROCESSING}, volume={25}, number={5}, booktitle={Ceramic Engineering and Science Proceedings}, author={Polotai, AV and Cheng, J and Agrawal, DK and Dickey, EC and Cytron, S}, year={2008}, pages={127-+} }
 @article{yang_moses_dickey_randall_2008, title={Site-Specific Studies of Electrical Heterogeneities in Ni-BaTiO3 Multilayer Ceramic Capacitors Using FIB and AEM}, volume={14}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927608082895}, DOI={10.1017/S1431927608082895}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 – August 7, 2008}, number={S2}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Yang, GY and Moses, PJ and Dickey, EC and Randall, CA}, year={2008}, month={Aug}, pages={992–993} }
 @article{dickey_clark_zhang_redwing_2008, title={Size Effects in the Vapor-Liquid Solid (VLS) Growth of Semiconductor Nanowires}, volume={14}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/s1431927608087382}, DOI={10.1017/s1431927608087382}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 – August 7, 2008}, number={S2}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Dickey, EC and Clark, TE and Zhang, X and Redwing, JM}, year={2008}, month={Aug}, pages={6–7} }
 @inbook{polotai_shay_yang_dickey_randall_2008, title={Stability of Ni Electrodes and Ni-BaTiO3 Interface Evolution in Ultrathin BME MLCCs}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000270584000002&KeyUID=WOS:000270584000002}, booktitle={2008 17th Ieee International Symposium on the Applications of Ferroelectrics}, author={Polotai, AV and Shay, DP and Yang, GY and Dickey, EC and Randall, CA}, year={2008}, pages={3–4} }
 @inproceedings{polotai_shay_yang_dickey_randall_2008, title={Stability of Ni Electrodes and Ni-BaTiO3 Interface Evolution in Ultrathin BME MLCCs}, booktitle={2008 17TH IEEE INTERNATIONAL SYMPOSIUM ON THE APPLICATIONS OF FERROELECTRICS}, author={Polotai, AV and Shay, DP and Yang, G-Y and Dickey, EC and Randall, CA}, year={2008}, pages={3–4} }
 @inproceedings{polotai_shay_yang_dickey_randall_2008, title={Stability of Ni electrodes and Ni-BaTiO<inf>3</inf> interface evolution in ultrathin BME MLCCs}, volume={1}, url={https://app.dimensions.ai/details/publication/pub.1095119126}, DOI={10.1109/ISAF.2008.4693884}, abstractNote={Microstructural control in thin-layer multilayer ceramic capacitors (MLCC) is one of the present day challenges for maintaining an increase in capacitive volumetric efficiency. It is observed that the continuity of the Ni electrodes increases with increasing heating rate but behaves non-linearly on sintering temperature. It is proposed that an interfacial liquid alloy layer initiates when the Ni electrodes are under tension. This accelerates a stress-induced diffusion which is the key cause of the severe electrode discontinuities during heating. Kinetic and thermodynamic approaches based on the control of sintering profiles or the control of Ni-BaTiO3 interface chemistry are proposed to prevent the Ni electrode discontinuity.}, booktitle={IEEE International Symposium on Applications of Ferroelectrics}, author={Polotai, AV and Shay, DP and Yang, GY and Dickey, EC and Randall, CA}, year={2008}, month={Dec} }
 @article{li_gauntt_dickey_2008, title={TEM Characterization of Microtwins in VOx thin films}, volume={14}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927608086790}, DOI={10.1017/S1431927608086790}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 – August 7, 2008}, number={S2}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Li, J and Gauntt, BD and Dickey, EC}, year={2008}, month={Aug}, pages={226–227} }
 @article{li_schulze_bharadwaja_dickey_trolier-mckinstry_2008, title={TEM Characterization of Nanometer-Scale Spinel /Rocksalt Phase Decomposition in Nickel Magnanite Thin Film}, volume={14}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927608086170}, DOI={10.1017/S1431927608086170}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2008 in Albuquerque, New Mexico, USA, August 3 – August 7, 2008}, number={S2}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Li, J and Schulze, H and Bharadwaja, SSN and Dickey, EC and Trolier-McKinstry, S}, year={2008}, month={Aug}, pages={228–229} }
 @article{clark_zhang_lew_pan_nimmatoori_redwing_dickey_2007, title={Diameter Dependence of Ge-doped Si Nanowires Fabricated via Vapor-Liquid-Solid Growth}, volume={13}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S143192760707804X}, DOI={10.1017/S143192760707804X}, number={S02}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Clark, TE and Zhang, X and Lew, K-K and Pan, L and Nimmatoori, P and Redwing, JM and Dickey, EC}, year={2007}, month={Aug}, pages={784–785} }
 @article{zhang_lew_nimmatoori_redwing_dickey_2007, title={Diameter-dependent composition of vapor-liquid-solid grown Si1-xGex nanowires}, volume={7}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000250143400054&KeyUID=WOS:000250143400054}, DOI={10.1021/nl071132u}, abstractNote={Diameter-dependent compositions of Si1-xGex nanowires grown by a vapor−liquid−solid mechanism using SiH4 and GeH4 precursors are studied by transmission electron microscopy and X-ray energy dispersive spectroscopy. For the growth conditions studied, the Ge concentration in Si1-xGex nanowires shows a strong dependence on nanowire diameter, with the Ge concentration decreasing with decreasing nanowire diameter below ∼50 nm. The size-dependent nature of Ge concentration in Si1-xGex NWs is strongly suggestive of Gibbs−Thomson effects and highlights another important phenomenon in nanowire growth.}, number={10}, journal={Nano Letters}, author={Zhang, X and Lew, KK and Nimmatoori, P and Redwing, JM and Dickey, EC}, year={2007}, pages={3241–3245} }
 @article{zhang_kulik_dickey_2007, title={Diffusion in SixGe1-x/Si nanowire heterostructures}, volume={7}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000243514900052&KeyUID=WOS:000243514900052}, DOI={10.1166/jnn.2007.155}, abstractNote={Si 0.48 Ge 0.52 /Si tip/nanowire heterostructures were grown by pulsed laser vaporization (PLV) at a growth temperature of 1100 °C. Ge diffusion in [111]-growth Si nanowires was studied for different post-synthesis annealing temperatures from 200 °C to 800 °C. Ge composition profiles were quantified by energy-dispersive X-ray spectroscopy in a transmission electron microscope. The compositional profiles were modeled by a limited-source diffusion model to extract temperature-dependent diffusion coefficients. The Ge diffusion coefficients followed an Arrhenius relationship with an activation energy of 0.622 ± 0.050 eV. This rather low activation energy barrier is similar to the previously reported activation energy barrier of 0.67 eV for Ge surface diffusion on Si, suggesting that surface diffusion may dominate in nanowires at this length scale.}, number={2}, journal={Journal of Nanoscience and Nanotechnology}, author={Zhang, Xi and Kulik, Joseph and Dickey, Elizabeth C.}, year={2007}, pages={717–720} }
 @article{polotai_jeong_yang_dickey_randall_pinceloup_gurav_2007, title={Effect of Cr additions on the microstructural stability of Ni electrodes in ultra-thin BaTiO3 multilayer capacitors}, volume={18}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000248625300012&KeyUID=WOS:000248625300012}, DOI={10.1007/s10832-007-9124-4}, number={3-4}, journal={Journal of Electroceramics}, author={Polotai, AV and Jeong, TH and Yang, GY and Dickey, EC and Randall, CA and Pinceloup, P and Gurav, AS}, year={2007}, pages={261–268} }
 @article{morita_mizuno_chazono_kishi_yang_liu_dickey_randall_2007, title={Electric conduction of thin-layer Ni-multilayer ceramic capacitors with core-shell structure BaTiO3}, volume={46}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000246781100035&KeyUID=WOS:000246781100035}, DOI={10.1143/JJAP.46.2984}, abstractNote={The electric conduction mechanism for multilayer ceramic capacitors with Ni internal electrodes (Ni-MLCCs) was investigated, utilizing impedance spectroscopy (IS) and thermally stimulated current (TSC) measurement techniques. A modified 4RC equivalent circuit model was proposed to analyze the IS data for the Ni-MLCCs. This model revealed that electrode/ceramics interfaces (E/C-I) and grain boundaries (GBs) have a Schottky type conduction mechanism controlling the leakage behavior at low electric field. The Schottky barrier height at E/C-I and surface level height at GB were calculated being 1.43 and 1.06 eV, respectively. The Ni-MLCCs showed a tunneling conduction occurs with high dc electric fields of more than 10 V/µm. The onset electric field for the tunneling conduction shifted toward high electric fields as the Mn content of the capacitors increased. TSC measurements revealed that a low Mn content resulted in high mobile oxygen vacancies concentration in the Ni-MLCCs. Mn also played a role in preventing oxygen vacancies from migrating to cathode electrodes, which resulted in a long lifetime for the Ni-MLCCs.}, number={5A}, journal={Japanese Journal of Applied Physics Part 1-Regular Papers Brief Communications & Review Papers}, author={Morita, K and Mizuno, Y and Chazono, H and Kishi, H and Yang, GY and Liu, WE and Dickey, EC and Randall, CA}, year={2007}, pages={2984–2990} }
 @article{weng_acord_jain_dickey_redwing_2007, title={Evolution of threading dislocation density and stress in GaN films grown on (111) Si substrates by metalorganic chemical vapor deposition}, volume={36}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000246861600013&KeyUID=WOS:000246861600013}, DOI={10.1007/s11664-006-0055-7}, number={4}, journal={Journal of Electronic Materials}, author={Weng, X and Acord, JD and Jain, A and Dickey, EC and Redwing, JM}, year={2007}, pages={346–352} }
 @article{weng_raghavan_acord_jain_dickey_redwing_2007, title={Evolution of threading dislocations in MOCVD-grown GaN films on (111) Si substrates}, volume={300}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000245368700045&KeyUID=WOS:000245368700045}, DOI={10.1016/j.jcrysgro.2006.11.030}, abstractNote={We have quantitatively compared the evolution of threading dislocations (TDs) in GaN films grown on (1 1 1) Si substrates using different buffer/interlayer structures: a compositionally graded AlxGa1−xN (0⩽x⩽1) buffer layer, a thin high-temperature (HT) AlN interlayer (IL), and an AlN/GaN/AlxGa1−xN multilayer. Plan-view transmission electron microscopy (TEM) shows a reduction in TD density in GaN films grown on graded AlxGa1−xN buffer layers, and an increase in TD density in GaN films grown on HT AlN ILs, in comparison with those grown directly on an AlN buffer layer. Cross-sectional TEM reveals bending and annihilation of TDs within the graded AlxGa1−xN buffer layer, which lead to a decrease of TD density in the overgrown GaN films. On the other hand, a high density of TDs forms at the GaN/AlN IL interface, resulting in an increase in TD density in the GaN film. In addition, growing a thin AlN+GaN bilayer before growing the compositionally graded AlxGa1−xN buffer layer significantly reduces the TD density in the AlxGa1−xN buffer layer, which subsequently further reduces the TD density in the overgrown GaN film.}, number={1}, journal={Journal of Crystal Growth}, author={Weng, X and Raghavan, S and Acord, JD and Jain, A and Dickey, EC and Redwing, JM}, year={2007}, pages={217–222} }
 @article{olszta_sloppy_li_dickey_2007, title={Field-Induced Crystallization of Anodized Nb and NbO Electrolytic Capacitors}, volume={13}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927607077628}, DOI={10.1017/S1431927607077628}, abstractNote={Extract Extended abstract of a paper presented at Microscopy and Microanalysis 2007 in Ft. Lauderdale, Florida, USA, August 5 – August 9, 2007}, number={S02}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Olszta, M and Sloppy, J and Li, J and Dickey, E}, year={2007}, month={Aug}, pages={810–811} }
 @article{li_olszta_dickey_2007, title={Fluctuation Electron Microscopy Investigation of Anodic Ta2O5 and Nb2O5 Dielectrics}, volume={13}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927607076271}, DOI={10.1017/S1431927607076271}, abstractNote={Extract Extended abstract of a paper presented at Microscopy and Microanalysis 2007 in Ft. Lauderdale, Florida, USA, August 5 – August 9, 2007}, number={S02}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Li, J and Olszta, M and Dickey, EC}, year={2007}, month={Aug}, pages={1002–1003} }
 @article{wang_varghese_grimes_dickey_2007, title={Grain boundary blocking and segregation effects in yttrium-doped polycrystalline titanium dioxide}, volume={178}, ISSN={0167-2738}, url={http://dx.doi.org/10.1016/j.ssi.2006.12.006}, DOI={10.1016/j.ssi.2006.12.006}, abstractNote={Impedance spectroscopy was used to investigate the electrical behavior of undoped, 0.025 mol% and 0.1 mol% yttrium-doped polycrystalline TiO 2 . In the doped samples, distinct contributions from the bulk and grain boundaries to the electronic conduction were evident, while no grain boundary blocking effect was observed in pure titania samples. The activation energy for grain boundary electronic conduction increased with increasing dopant concentration, which implied an increasing barrier height in these regions introduced by the solute interfacial excess. The impedance behavior was correlated with grain boundary solute segregation measurements and rationalized in terms of the local grain boundary defect chemistry in the grain boundary cores and space-charge layers.}, number={3-4}, journal={Solid State Ionics}, publisher={Elsevier BV}, author={Wang, Q and Varghese, O and Grimes, C and Dickey, E}, year={2007}, month={Feb}, pages={187–194} }
 @article{yang_polotai_dickey_randall_2007, title={HRTEM and EELS Study of Ni-BaTiO3 Interfacial Reactions Kinetics}, volume={13}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S143192760707239X}, DOI={10.1017/S143192760707239X}, number={S02}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Yang, GY and Polotai, AV and Dickey, EC and Randall, CA}, year={2007}, month={Aug}, pages={800–801} }
 @article{deng_dickey_paderno_paderno_filippov_2007, title={Interface Crystallography and structure in LaB6-ZrB2 directionally solidified eutectics}, volume={90}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000248379600047&KeyUID=WOS:000248379600047}, DOI={10.1111/j.1551-2916.2007.01812.x}, abstractNote={Interfaces in LaB6–ZrB2 composites directionally solidified by a zone melting process were characterized by transmission electron microscopy (TEM). The nominal crystallographic orientation relationship between the two phases corresponded to a high-symmetry near-coincidence site lattice (NCSL). The small mistilt (2°–5°) from the high-symmetry orientation relationship was shown to result in an increased volume density of coincident sites. Furthermore, the dominant interface facet planes were predicted by the NCSL model. The configurations of interfacial misfit dislocations were analyzed by high-resolution TEM and showed a good agreement with predictions based on the displacement shift complete lattice and secondary original lattice (O2-lattice) models. These analyses suggested that interfaces were relaxed to relatively low-energy configurations.}, number={8}, journal={Journal of the American Ceramic Society}, author={Deng, H and Dickey, EC and Paderno, Y and Paderno, V and Filippov, V}, year={2007}, pages={2603–2609} }
 @article{yang_moses_dickey_randall_2007, title={Local impedance and microchemical analysis of electrical heterogeneities in multilayer electroceramic devices}, volume={22}, ISSN={0884-2914 2044-5326}, url={http://dx.doi.org/10.1557/JMR.2007.0443}, DOI={10.1557/JMR.2007.0443}, number={12}, journal={Journal of Materials Research}, publisher={Cambridge University Press (CUP)}, author={Yang, G.Y. and Moses, P.J. and Dickey, E.C. and Randall, C.A.}, year={2007}, month={Dec}, pages={3507–3515} }
 @article{mgb2 thin films by hybrid physical-chemical vapor deposition_2007, volume={456}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000247489700004&KeyUID=WOS:000247489700004}, DOI={10.1016/j.physc.2007.01.029}, abstractNote={Hybrid physical–chemical vapor deposition (HPCVD) has been the most effective technique for depositing MgB2 thin films. It generates high magnesium vapor pressures and provides a clean environment for the growth of high purity MgB2 films. The epitaxial pure MgB2 films grown by HPCVD show higher-than-bulk Tc due to tensile strain in the films. The HPCVD films are the cleanest MgB2 materials reported, allowing basic research, such as on magnetoresistance, that reveals the two-band nature of MgB2. The carbon-alloyed HPCVD films demonstrate record-high Hc2 values promising for high magnetic field applications. The HPCVD films and multilayers have enabled the fabrication of high quality MgB2 Josephson junctions.}, number={1-2}, journal={Physica C-Superconductivity and Its Applications}, year={2007}, pages={22–37} }
 @article{he_behera_finnis_li_dickey_phillpot_sinnott_2007, title={Prediction of high-temperature point defect formation in TiO2 from combined ab initio and thermodynamic calculations}, volume={55}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000248436400009&KeyUID=WOS:000248436400009}, DOI={10.1016/j.actamat.2007.04.005}, abstractNote={Abstract A computational approach that integrates ab initio electronic structure and thermodynamic calculations is used to determine point defect stability in rutile TiO 2 over a range of temperatures, oxygen partial pressures and stoichiometries. Both donors (titanium interstitials and oxygen vacancies) and acceptors (titanium vacancies) are predicted to have shallow defect transition levels in the electronic-structure calculations. The resulting defect formation energies for all possible charge states are then used in thermodynamic calculations to predict the influence of temperature and oxygen partial pressure on the relative stabilities of the point defects. Their ordering is found to be the same as temperature increases and oxygen partial pressure decreases: titanium vacancy → oxygen vacancy → titanium interstitial. The charges on these defects, however, are quite sensitive to the Fermi level. Finally, the combined formation energies of point defect complexes, including Schottky, Frenkel and anti-Frenkel defects, are predicted to limit the further formation of point defects.}, number={13}, journal={Acta Materialia}, author={He, J and Behera, RK and Finnis, MW and Li, X and Dickey, EC and Phillpot, SR and Sinnott, SB}, year={2007}, pages={4325–4337} }
 @article{srinivasan_mullen_hohman_anderson_dameron_andrews_dickey_horn_weiss_2007, title={Scanning electron microscopy of nanoscale chemical patterns}, volume={1}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000252145100009&KeyUID=WOS:000252145100009}, DOI={10.1021/nn7000799}, abstractNote={A series of nanoscale chemical patterning methods based on soft and hybrid nanolithographies have been characterized using scanning electron microscopy with corroborating evidence from scanning tunneling microscopy and lateral force microscopy. We demonstrate and discuss the unique advantages of the scanning electron microscope as an analytical tool to image chemical patterns of molecules highly diluted within a host self-assembled monolayer and to distinguish regions of differential mass coverage in patterned self-assembled monolayers. We show that the relative contrast of self-assembled monolayer patterns in scanning electron micrographs depends on the operating primary electron beam voltage, monolayer composition, and monolayer order, suggesting that secondary electron emission and scattering can be used to elucidate chemical patterns.}, number={3}, journal={Acs Nano}, author={Srinivasan, C and Mullen, TJ and Hohman, JN and Anderson, ME and Dameron, AA and Andrews, AM and Dickey, EC and Horn, MW and Weiss, PS}, year={2007}, pages={191–201} }
 @inproceedings{redwing_acord_manning_raghavan_weng_dickey_snyder_2007, title={Stress and morphology evolution during the heteroepitaxial growth of group III-nitrides}, url={https://app.dimensions.ai/details/publication/pub.1093590299}, DOI={10.1109/ISDRS.2007.4422504}, abstractNote={In this study, in-situ wafer curvature measurements were used to monitor the evolution of film stress during MOCVD growth of GaN and AlGaN. These studies were carried out using a multi- beam optical stress sensor (MOSS) incorporated onto a custom-designed vertical cold-wall MOCVD reactor. The MOSS system provides real-time information on growth rate and changes in substrate curvature which are related to film stress via a modified version of Stoney's equation. Post-growth structural characterization including atomic force microscopy, X-ray diffraction and transmission electron microscopy was used to correlate measured changes in film stress to film morphology evolution.}, booktitle={2007 International Semiconductor Device Research Symposium, ISDRS}, author={Redwing, JM and Acord, JD and Manning, I and Raghavan, S and Weng, X and Dickey, EC and Snyder, DW}, year={2007}, month={Dec}, pages={535-+} }
 @book{redwing_acord_manning_raghavan_weng_dickey_snyder_2007, title={Stress and morphology evolution during the heteroepitaxial growth of group III-nitrides}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000255857100276&KeyUID=WOS:000255857100276}, journal={2007 International Semiconductor Device Research Symposium, Vols 1 and 2}, author={Redwing, JM and Acord, JD and Manning, I and Raghavan, S and Weng, X and Dickey, EC and Snyder, DW}, year={2007}, pages={535–536} }
 @article{lueking_gutierrez_fonseca_dickey_2007, title={Structural characterization of exfoliated graphite nanofibers}, volume={45}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000245310100010&KeyUID=WOS:000245310100010}, DOI={10.1016/j.carbon.2006.11.023}, abstractNote={Abstract Structural characterization of exfoliated graphite nanofibers (EGNFs) with transmission electron microscopy (TEM) and high-angle annular dark-field–scanning TEM (HAADF–STEM) indicates exfoliation has led to structural expansion along the fiber axis, with discrete domains of graphitic nanocones separated by gaps ranging from 50 to 500 A. Image contrast in HAADF–STEM demonstrates that structural expansion dominates over chemical etching. Raman spectroscopy indicates the EGNF is more graphitic than the precursor, and the disappearance of the characteristic defect (D) peak with multi-wavelength excitation is inconsistent with the presence of amorphous carbon. The highly expanded EGNF structure oxidizes at two distinct rates at 750 °C in CO2, leading to a highly-disordered graphitic fiber, with apparent collapse of the expanded structure as no gaps or discrete graphitic domains are observed after oxidation. Variation in the heat input per intercalant mass during thermal shock leads to changes in fiber morphology, including the extent of fiber expansion, the number of defects and pores observable within the fiber via TEM, and the surface area measured by nitrogen adsorption.}, number={4}, journal={Carbon}, author={Lueking, AD and Gutierrez, HR and Fonseca, DA and Dickey, E}, year={2007}, pages={751–759} }
 @inproceedings{sethi_olszta_li_sloppy_horn_dickey_lanagan_2007, title={Structure and dielectric properties of amorphous tantalum pentoxide thin film capacitors}, url={https://app.dimensions.ai/details/publication/pub.1095576222}, DOI={10.1109/CEIDP.2007.4451491}, abstractNote={Amorphous tantalum pentoxide films are currently being studied as a high-k dielectric for high energy-density Metal-Insulator-Metal capacitors. Tantalum pentoxide thin films were prepared through pulsed-dc reactive magnetron sputtering at a high deposition rate (15 Å/s). The films were amorphous as determined by X-ray and electron diffraction through Transmission Electron Microscopy (TEM) at all sputtering conditions of both low and high ion bombardments unlike other oxides such as zirconium oxide. The structure was also confirmed by electron energy loss spectra using anodized Ta <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> O <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</inf> films as a benchmark. After annealing at 750 °C, the films crystallized to the β-Ta <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> O <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</inf> phase (x-ray analysis). The dielectric constant and loss of the 2μm-thick films are 21 and 0.3%, respectively, at 1 kHz at room temperature of 25 °C. The amorphous films have a Temperature Coefficient of dielectric constant (TCK) of 2.1×10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−3</sup> °C <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">−1</sup> , similar to crystalline forms of Ta <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> O <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</inf> namely, α-Ta <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> O <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</inf> and β-Ta <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> O <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">5</inf> . Electrical breakdown field of these amorphous tantalum pentoxide films is as high as 400 MV/m with a corresponding energy density of 14 J/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> . Electrical breakdown is affected by material crystallinity, which is controlled by annealing. The crystallinity is studied both at bulk level through X-Ray diffraction and at the local atomic level through Fluctuation Electron Microscopy (FEM), which is an electron microscopy technique used to study Medium Range Order (MRO) on the length scale of 1–3 nm in apparently diffraction amorphous (TEM and X-ray) materials.}, booktitle={Annual Report Conference on Electrical Insulation and Dielectric Phenomena}, author={Sethi, G and Olszta, M and Li, J and Sloppy, J and Horn, MW and Dickey, EC and Lanagan, MT}, year={2007}, pages={815–818} }
 @book{sethi_olszta_li_sloppy_horn_dickey_lanagan_2007, title={Structure and dielectric properties of amorphous tantalum pentoxide thin film capacitors}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000254276700197&KeyUID=WOS:000254276700197}, journal={2007 Annual Report Conference on Electrical Insulation and Dielectric Phenomena}, author={Sethi, G and Olszta, M and Li, J and Sloppy, J and Horn, MW and Dickey, EC and Lanagan, MT}, year={2007}, pages={815–818} }
 @inproceedings{randall_kinard_qazi_hahn_lessner_trolier-mckinstry_ko_lu_dechakupt_randall_et al._2007, title={The battle for maximum volumetric efficiency - Part 2: Advancements in solid electrolyte capacitors}, booktitle={CARTS Europe 2007}, author={Randall, M and Kinard, T and Qazi, J and Hahn, R and Lessner, P and Trolier-McKinstry, S and Ko, SW and Lu, SG and Dechakupt, T and Randall, CA and et al.}, year={2007}, month={Dec}, pages={11–22} }
 @article{polotai_yang_dickey_randall_2007, title={Utilization of multiple-stage sintering to control ni electrode continuity in ultrathin Ni-BaTiO3 multilayer capacitors}, volume={90}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000251504300014&KeyUID=WOS:000251504300014}, DOI={10.1111/j.1551-2916.2007.02058.x}, abstractNote={Microstructural control in thin-layer multilayer ceramic capacitors (MLCCs) is one of the present-day challenges for maintaining an increase in capacitive volumetric efficiency. The present paper continues a series of investigations aimed at understanding and controlling the microstructural stability of ultrathin Ni electrodes in MLCCs. Here, a kinetic approach based on the control of sintering profiles is used. Ni–BaTiO3 MLCC chips (0805-type with 300 active layers) are nonisothermally sintered up to 900°–1300°C with different heating rates in the range from 200° to 3000°C/h. In general, the continuity of the Ni electrodes increases with heating rate. However, a strong nonlinear dependence of Ni electrode continuity on sintering temperature is observed. It is concluded that a low-melting interfacial liquid (Ni,Ba,Ti) alloy layer initiates at temperatures between 1000° and 1100°C when the Ni electrodes are under tension. This interfacial liquid phase accelerates a stress-induced diffusion and is the key cause of the severe electrode discontinuities during heating. At higher temperatures (above 1100°C), where compressive stresses are active, the interfacial liquid alloy layer facilitates some recovery of the Ni electrode microstructure. The formation of the interfacial liquid alloy layer can be kinetically controlled using fast-heating rates, which improves the Ni electrode continuity.}, number={12}, journal={Journal of the American Ceramic Society}, author={Polotai, AV and Yang, GY and Dickey, EC and Randall, CA}, year={2007}, pages={3811–3817} }
 @article{raghavan_weng_dickey_redwing_2006, title={Correlation of growth stress and structural evolution during metalorganic chemical vapor deposition of GaN on (111) Si}, volume={88}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000234968600027&KeyUID=WOS:000234968600027}, DOI={10.1063/1.2168020}, abstractNote={Compositionally graded AlGaN buffer layers enable the growth of thicker crack free layers of GaN on (111) Si than is possible with an AlN buffer layer. Using cross sectional transmission electron microscopy and in situ stress measurements, it is shown that a compressive growth stress is incorporated in the GaN layer when the graded AlGaN buffer layer is thick enough to accommodate all microstructural evolution, which is primarily a reduction in threading dislocation density with thickness during growth. Most of the dislocation density reduction is observed to occur when the film is growing under a compressive stress. This compressive stress arises from the changing lattice parameter due to grading and helps to offset the tensile stress generated by microstructural evolution. It also helps to decrease the tensile thermal expansion mismatch stress during cooling and thus reduces film cracking.}, number={4}, journal={Applied Physics Letters}, author={Raghavan, S and Weng, XJ and Dickey, E and Redwing, JM}, year={2006} }
 @article{zhang_kulik_dickey_2006, title={Diffusion in SixGe1-x/ Si Nanowire Heterostructures}, volume={12}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S143192760606586X}, DOI={10.1017/S143192760606586X}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006}, number={S02}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Zhang, X and Kulik, J and Dickey, E}, year={2006}, month={Jul}, pages={520–521} }
 @article{lew_pan_dickey_redwing_2006, title={Effect of growth conditions on the composition and structure of Si1-xGex nanowires grown by vapor-liquid-solid growth}, volume={21}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000241843300019&KeyUID=WOS:000241843300019}, DOI={10.1557/JMR.2006.0349}, number={11}, journal={Journal of Materials Research}, author={Lew, KK and Pan, L and Dickey, EC and Redwing, JM}, year={2006}, pages={2876–2881} }
 @article{yang_lee_liu_anthony_dickey_liu_randall_2006, title={Effect of local oxygen activity on Ni-BaTiO3 interfacial reactions}, volume={54}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000239823800012&KeyUID=WOS:000239823800012}, DOI={10.1016/j.actamat.2006.03.025}, abstractNote={This investigation discovers a discrete metallic alloy layer containing Ni, Ti, and Ba between Ni and BaTiO3 co-fired in reducing atmospheres at ∼1300 °C along with an oxygen-depleted zone in BaTiO3 adjacent to the metallic layer. Using high-resolution transmission electron microscopy and electron energy-loss spectroscopy, detailed structural and chemical analyses of the metallic layer are carried out. With complementary thermodynamic approximations, these observations render an assessment of the local effective oxygen partial pressure, which is considerably lower than the external, ambient processing environment. Through a set of model experiments on Ni–BaTiO3–carbon composites, we illustrate that the presence of carbon is sufficient to reduce locally BaTiO3 and form the observed metallic layer at ∼1300 °C. A phase stability analysis indicates that the formation of the Ba and Ni–Ti liquid phases provides a kinetic path for the interfacial reaction.}, number={13}, journal={Acta Materialia}, author={Yang, GY and Lee, SI and Liu, ZJ and Anthony, CJ and Dickey, EC and Liu, ZK and Randall, CA}, year={2006}, pages={3513–3523} }
 @article{weng_acord_jain_raghavan_redwing_dickey_2006, title={Evolution of Threading Dislocations in GaN Films Grown on (111) Si Substrates with Various Buffer Layers}, volume={12}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927606065524}, DOI={10.1017/S1431927606065524}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2006}, number={S02}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Weng, X and Acord, J and Jain, A and Raghavan, S and Redwing, J and Dickey, E}, year={2006}, month={Jul}, pages={906–907} }
 @article{olszta_dougherty_horn_dickey_2006, title={Focused Ion Beam (FIB) Preparation and Electron Microscopy Analysis of Individual Microbolometer Pixels}, volume={12}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927606068747}, DOI={10.1017/S1431927606068747}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2005}, number={S02}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Olszta, M and Dougherty, J and Horn, M and Dickey, EC}, year={2006}, month={Jul}, pages={1270–1271} }
 @article{fox_hellmann_dickey_green_shelleman_yeckley_2006, title={Impression and compression creep of SiAlON ceramics}, volume={89}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000239005900030&KeyUID=WOS:000239005900030}, DOI={10.1111/j.1551-2916.2006.01100.x}, abstractNote={Concurrent impression and uniaxial compression creep studies were performed on three Yb-SiAlON materials. Stress exponents were approximately 1 in compression and 2 in impression. The higher stress exponents were due to the complex stress field in the impression creep test, which caused microstructural dilation. The dilated multi-grain junctions also became filled with additional intergranular glassy phase. Focused ion beam milling and in situ lift-out specimen preparation combined with transmission electron microscopy was successful in identifying microstructural changes after creep testing. These observations have important implications in the design of creep-resistant materials in complex stress fields.}, number={8}, journal={Journal of the American Ceramic Society}, author={Fox, KM and Hellmann, JR and Dickey, EC and Green, DJ and Shelleman, DL and Yeckley, RL}, year={2006}, pages={2555–2563} }
 @inproceedings{dickey_yang_wang_randall_2006, title={Interfacial defect chemistry in metal oxides: Complementary transmission electron microscopy and impedance spectroscopy studies}, volume={PV 2003-31}, booktitle={Proceedings - Electrochemical Society}, author={Dickey, EC and Yang, G and Wang, Q and Randall, CA}, year={2006}, month={Jul}, pages={187–196} }
 @article{planar mgb2 superconductor-normal metal-superconductor josephson junctions fabricated using epitaxial mgb2/tib2 bilayers_2006, volume={88}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000238001900060&KeyUID=WOS:000238001900060}, DOI={10.1063/1.2208555}, abstractNote={We have fabricated planar superconductor-normal metal-superconductor MgB2 Josephson junctions using TiB2 as the barrier material. On a bilayer film of MgB2∕TiB2 on SiC substrate, MgB2 was locally removed to create a gap of ⩽50nm, separating the MgB2 film into two electrodes. A Josephson coupling is established through the TiB2 film across the gap by proximity effect. The junctions exhibit resistively shunted junction like current-voltage characteristics up to 31K. An ac Josephson effect was observed and the behavior of the Shapiro steps are in good agreement with theoretical predictions. The magnetic field modulation of the critical current also agrees with the thin film planar junction behavior.}, number={22}, journal={Applied Physics Letters}, year={2006} }
 @article{olszta_wang_dickey_2006, title={Stoichiometry and valence measurements of niobium oxides using electron energy-loss spectroscopy}, volume={224}, url={https://app.dimensions.ai/details/publication/pub.1050161649}, DOI={10.1111/j.1365-2818.2006.01709.x}, abstractNote={Qualitative and quantitative electron energy-loss spectroscopy analyses have been performed on niobium and stable niobium oxides (NbO, NbO2 and Nb2O5). At integration windows (Δ) greater than 75 eV, k-factor analysis can be used to distinguish between the stoichiometry of the three oxides within 5.7% error. As seen in other metal oxides, with increasing oxidation state the metal ionization edges shift to higher energies relative to the O-K edge. Normalized M2,3 white-line intensities show a strong correlation with 4d occupancy for each compound. The data are in correspondence with that observed in the literature for 4d transition metals using normalized L2,3 white lines. Lastly, a distinctive energy-loss near-edge, structure of the O-K edge was observed for each oxide, which could be used as a fingerprint for analysis of unknowns.}, journal={Journal of Microscopy}, author={Olszta, MJ and Wang, J and Dickey, EC}, year={2006}, pages={233–241} }
 @inbook{weng_raghavan_dickey_redwing_2006, title={Stress and microstructure evolution in compositionally graded Al1-xGaxN buffer layers for GaN growth on Si}, volume={892}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000237224500004&KeyUID=WOS:000237224500004}, booktitle={GaN, AIN, InN and Related Materials}, author={Weng, XJ and Raghavan, S and Dickey, EC and Redwing, JM}, year={2006}, pages={27–32} }
 @inproceedings{weng_raghavan_dickey_redwing_2006, title={Stress and microstructure evolution in compositionally graded Al1-xGaxN buffer layers for GaN growth on Si}, volume={892}, booktitle={MRS Online Proceedings Library}, author={Weng, X and Raghavan, S and Dickey, EC and Redwing, JM}, year={2006}, pages={27-+} }
 @article{olszta_sloppy_wang_dickey_2006, title={TEM and EELS Analysis of Anodized Nb2O5: Stoichiometry and Field-Induced Crystallization}, volume={12}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S143192760606870X}, DOI={10.1017/S143192760606870X}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2005}, number={S02}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Olszta, M and Sloppy, J and Wang, J and Dickey, EC}, year={2006}, month={Jul}, pages={1194–1195} }
 @article{yang_dickey_randall_2006, title={TEM and EELS Study of Dislocation Loops in Reduced BaTiO3}, volume={12}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927606068814}, DOI={10.1017/S1431927606068814}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2006 in Chicago, Illinois, USA, July 30 – August 3, 2005}, number={S02}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Yang, GY and Dickey, EC and Randall, CA}, year={2006}, month={Jul}, pages={1088–1089} }
 @article{polotai_breece_dickey_randall_ragulya_2005, title={A novel approach to sintering nanocrystalline barium titanate ceramics}, volume={88}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000232773100004&KeyUID=WOS:000232773100004}, DOI={10.1111/j.1551-2916.2005.00552.x}, abstractNote={A novel approach to pressureless sintering based on the combination of rapid-rate sintering, rate-controlled sintering, and two-step sintering under a controlled atmosphere is proposed. This combined sintering method facilitates control of grain and pore morphology. The application of this sintering approach for pure nanocrystalline barium titanate powder enables the suppression of grain growth during the intermediate and final stages of sintering and the production of fully dense ceramics with 108 nm grain size. The grain growth factor is 3.5, which is three and 17 times smaller than rate-controlled and conventional sintering, respectively.}, number={11}, journal={Journal of the American Ceramic Society}, author={Polotai, A and Breece, K and Dickey, E and Randall, C and Ragulya, A}, year={2005}, pages={3008–3012} }
 @article{deng_dickey_paderno_paderno_filippov_2005, title={Crystallographic Orientation Relationships and Interface Structures in Directionally Solidified LaB6-ZrB2 Eutectics.}, volume={11 Suppl 2}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=MEDLINE&KeyUT=MEDLINE:24017730&KeyUID=MEDLINE:24017730}, DOI={10.1017/S1431927605503623}, abstractNote={Extract HTML view is not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button. Extended abstract of a paper presented at Microscopy and Microanalysis 2005 in Honolulu, Hawaii, USA, July 31--August 4, 2005}, number={S02}, journal={Microscopy and microanalysis : the official journal of Microscopy Society of America, Microbeam Analysis Society, Microscopical Society of Canada}, publisher={Oxford University Press (OUP)}, author={Deng, H and Dickey, E and Paderno, Y and Paderno, V and Filippov, V}, year={2005}, pages={1724–5} }
 @article{raghavan_weng_dickey_redwing_2005, title={Effect of AlN interlayers on growth stress in GaN layers deposited on (111) Si}, volume={87}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000232225700028&KeyUID=WOS:000232225700028}, DOI={10.1063/1.2081128}, abstractNote={Thin (∼10nm) AlN interlayers have previously been used to mitigate stress and cracking in GaN epitaxial layers grown on Si substrates. However, multiple AlN interlayers are typically required for the growth of thick (>1μm) GaN as the initial compressive mismatch stress introduced by the AlN interlayer transitions to a tensile stress within 0.5μm. To better understand the reasons for the transition, in situ monitoring and transmission electron microscopy have been used to study stress and structural evolution in undoped GaN layers deposited on high temperature (1050–1100°C) AlN interlayers by metal-organic chemical-vapor deposition. The results show that transition of the initial compressive stress to a final tensile stress is associated with a reduction in the density of dislocations introduced either by the pseudosubstrate or the interlayer itself.}, number={14}, journal={Applied Physics Letters}, author={Raghavan, S and Weng, XJ and Dickey, E and Redwing, JM}, year={2005} }
 @article{pan_lew_redwing_dickey_2005, title={Effect of diborane on the microstructure of boron-doped silicon nanowires}, volume={277}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000228737900068&KeyUID=WOS:000228737900068}, DOI={10.1016/j.jcrysgro.2005.01.091}, abstractNote={Boron-doped silicon (Si) nanowires, with nominal diameters of 80 nm, were grown via the vapor–liquid–solid (VLS) mechanism using gold (Au) as a catalyst and silane (SiH4) and diborane (B2H6) as precursors. The microstructure of the nanowires was studied by scanning electron microscopy, transmission electron microscopy and electron energy-loss spectroscopy. At lower B2H6 partial pressure and thus lower doping levels (⩽1×1018 cm−3), most of the boron-doped Si nanowires exhibited high crystallinity. At higher B2H6 partial pressure (∼2×1019 cm−3 doping level), the majority of the wires exhibited a core–shell structure with an amorphous Si shell (20–30 nm thick) surrounding a crystalline Si core. Au nanoparticles on the outer surface of the nanowires were also observed in structures grown with high B/Si gas ratios. The structural changes are believed to result from an increase in the rate of Si thin-film deposition on the outer surface of the nanowire at high B2H6 partial pressure, which produces the amorphous coating and also causes an instability at the liquid/solid interface resulting in a loss of Au during nanowire growth.}, number={1-4}, journal={Journal of Crystal Growth}, author={Pan, L and Lew, KK and Redwing, JM and Dickey, EC}, year={2005}, pages={428–436} }
 @inproceedings{jambunathan_liu_pan_dickey_shallenberger_smotkin_mallouk_2005, title={Electrocatalytic oxidation of methanol on high surface area unsupported catalysts}, volume={PV 2003-30}, booktitle={Proceedings - Electrochemical Society}, author={Jambunathan, K and Liu, R and Pan, L and Dickey, E and Shallenberger, J and Smotkin, E and Mallouk, T}, year={2005}, month={Dec}, pages={108–120} }
 @article{olszta_sloppy_wang_dickey_2005, title={Interfaces in Next Generation Ta and NbO Solid Electrolytic Capacitors.}, volume={11 Suppl 2}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=MEDLINE&KeyUT=MEDLINE:24017160&KeyUID=MEDLINE:24017160}, DOI={10.1017/S1431927605508122}, abstractNote={Extract HTML view is not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button. Extended abstract of a paper presented at Microscopy and Microanalysis 2005 in Honolulu, Hawaii, USA, July 31--August 4, 2005}, number={S02}, journal={Microscopy and microanalysis : the official journal of Microscopy Society of America, Microbeam Analysis Society, Microscopical Society of Canada}, publisher={Oxford University Press (OUP)}, author={Olszta, M and Sloppy, J and Wang, J and Dickey, E C}, year={2005}, pages={578–9} }
 @article{yang_dickey_randall_2005, title={Interfacial Reactions Between Ni and BaTiO3: An Analytical Transmission Electron Microscopy Study.}, volume={11 Suppl 2}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=MEDLINE&KeyUT=MEDLINE:24016988&KeyUID=MEDLINE:24016988}, DOI={10.1017/S1431927605502307}, number={SUPPL. 2}, journal={Microscopy and microanalysis : the official journal of Microscopy Society of America, Microbeam Analysis Society, Microscopical Society of Canada}, author={Yang, G Y and Dickey, E C and Randall, C A}, year={2005}, pages={232–3} }
 @inproceedings{randall_yang_dickey_eitel_shrout_lanagan_kwon_semouchkina_semouchkin_rhee_et al._2005, title={Present and future challenges in multilayer ceramic devices}, booktitle={Proceedings - 2005 IMAPS/ACerS 1st International Conference and Exhibition on Ceramic Interconnect and Ceramic Microsystems Technologies, CICMT 2005}, author={Randall, CA and Yang, G and Dickey, E and Eitel, RE and Shrout, TR and Lanagan, MT and Kwon, D and Semouchkina, E and Semouchkin, G and Rhee, S and et al.}, year={2005}, month={Dec}, pages={1–8} }
 @article{pan_lew_redwing_dickey_2005, title={Stranski-Krastanow growth of germanium on silicon nanowires}, volume={5}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000229729900016&KeyUID=WOS:000229729900016}, DOI={10.1021/nl050605z}, abstractNote={There have been extensive studies of germanium (Ge) grown on planar silicon (Si) substrates by the Stranski-Krastanow (S-K) mechanism. In this study, we present S-K growth of Ge on Si nanowires. The Si nanowires were grown at 500 degrees C by a vapor-liquid-solid (VLS) method, using silane (SiH4) as the gaseous precursor. By switching the gas source from SiH4 to germane (GeH4) during the growth and maintaining the growth conditions, epitaxial Ge islands deposited on the outer surface of the initially formed Si nanowires. Transmission electron microscopy (TEM), scanning TEM, and energy-dispersive X-ray spectroscopy techniques were utilized to identify the thin wetting layer and the three-dimensional Ge islands formed around the Si core nanowires. Cross-sectional TEM verified the surface faceting of the Si core nanowires as well as the Ge islands.}, number={6}, journal={Nano Letters}, author={Pan, L and Lew, KK and Redwing, JM and Dickey, EC}, year={2005}, pages={1081–1085} }
 @article{pan_lew_redwing_dickey_2005, title={Study on Axial and Radial Heterostructures of Si-Ge and Si-SiGe Nanowires.}, volume={11 Suppl 2}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=MEDLINE&KeyUT=MEDLINE:24017729&KeyUID=MEDLINE:24017729}, DOI={10.1017/S1431927605507505}, number={S02}, journal={Microscopy and microanalysis : the official journal of Microscopy Society of America, Microbeam Analysis Society, Microscopical Society of Canada}, publisher={Oxford University Press (OUP)}, author={Pan, L and Lew, K-K and Redwing, J and Dickey, E}, year={2005}, pages={1722–3} }
 @article{wang_lew_ho_pan_novak_dickey_redwing_mayer_2005, title={Use of phosphine as an n-type dopant source for vapor-liquid-solid growth of silicon nanowires}, volume={5}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000233481700005&KeyUID=WOS:000233481700005}, DOI={10.1021/nl051442h}, abstractNote={Phosphine (PH3) was investigated as an n-type dopant source for Au-catalyzed vapor-liquid-solid (VLS) growth of phosphorus-doped silicon nanowires (SiNWs). Transmission electron microscopy characterization revealed that the as-grown SiNWs were predominately single crystal even at high phosphorus concentrations. Four-point resistance and gate-dependent conductance measurements confirmed that electrically active phosphorus was incorporated into the SiNWs during VLS growth. A transition was observed from p-type conduction for nominally undoped SiNWs to n-type conduction upon the introduction of PH3 to the inlet gas. The resistivity of the n-type SiNWs decreased by approximately 3 orders of magnitude as the inlet PH3 to silane (SiH4) gas ratio was increased from 2 x 10(-5) to 2 x 10(-3). These results demonstrate that PH3 can be used to produce n-type SiNWs with properties that are suitable for electronic and optoelectronic device applications.}, number={11}, journal={Nano Letters}, author={Wang, YF and Lew, KK and Ho, TT and Pan, L and Novak, SW and Dickey, EC and Redwing, JM and Mayer, TS}, year={2005}, pages={2139–2143} }
 @article{wang_varghese_paulose_grimes_wang_dickey_2004, title={A study on the growth and structure of titania nanotubes}, volume={19}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000222316200004&KeyUID=WOS:000222316200004}, DOI={10.1557/jmr.2004.19.2.417}, number={2}, journal={Journal of Materials Research}, author={Wang, WZ and Varghese, OK and Paulose, M and Grimes, CA and Wang, QL and Dickey, EC}, year={2004}, pages={417–422} }
 @article{wang_varghese_paulose_grimes_wang_dickey_2004, title={A study on the growth and structure of titania nanotubes}, volume={19}, DOI={10.1557/jmr.2004.0048}, number={2}, journal={Journal of Materials Research}, author={Wang, W and Varghese, OK and Paulose, M and Grimes, CA and Wang, Q and Dickey, EC}, year={2004}, month={Jan}, pages={417–422} }
 @article{deng_dickey_paderno_paderno_filippov_sayir_2004, title={Crystallographic characterization and indentation mechanical properties of LaB6-ZrB2 directionally solidified eutectics}, volume={39}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000224895300011&KeyUID=WOS:000224895300011}, number={19}, journal={Journal of Materials Science}, author={Deng, H and Dickey, EC and Paderno, Y and Paderno, V and Filippov, V and Sayir, A}, year={2004}, pages={5987–5994} }
 @article{deng_dickey_paderno_paderno_filippov_sayir_2004, title={Crystallographic characterization and indentation mechanical properties of LaB6-ZrB2directionally solidified eutectics}, volume={39}, ISSN={0022-2461}, url={http://dx.doi.org/10.1023/B:JMSC.0000041695.40772.56}, DOI={10.1023/B:JMSC.0000041695.40772.56}, number={19}, journal={Journal of Materials Science}, publisher={Springer Science and Business Media LLC}, author={Deng, H. and Dickey, E. C. and Paderno, Y. and Paderno, V. and Filippov, V. and Sayir, A.}, year={2004}, month={Oct}, pages={5987–5994} }
 @article{furtado_kim_gutierrez_pan_dickey_eklund_2004, title={Debundling and dissolution of single-walled carbon nanotubes in amide solvents}, volume={126}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000221416700042&KeyUID=WOS:000221416700042}, DOI={10.1021/ja039588a}, abstractNote={Wet chemical methods involving ultrasound and amide solvents were used to purify and separate large bundles of single-walled carbon nanotubes (SWNTs) into individual nanotubes that could then be transported to silicon or mica substrates. The SWNTs studied were produced by the arc-discharge process. Dry oxidation was used in an initial step to remove amorphous carbon. Subsequently, two acid purification schemes were investigated (HCl- and HNO(3)-reflux) to remove the metal growth catalyst (Ni-Y). Finally, ultrasonic dispersion of isolated tubes into either N,N-dimethylformamide (DMF) or N-methyl-2-pyrrolidone (NMP) was carried out. Raman scattering, atomic force microscopy (AFM), and electron microscopy were used to study the evolution of the products. Raman scattering was used to probe possible wall damage during the chemical processing. We found that both HCl and HNO(3) could be used to successfully remove the Ni-Y below approximately 1 wt %. However, the HNO(3)-reflux produced significant wall damage (that could be reversed by vacuum annealing at 1000 degrees C). In the dispersion step, both amide solvents (DMF and NMP) produced a high degree of isolated tubes in the final product, and no damage during this dispersion step was observed. HNO(3)-refluxed tubes were found to disperse the best into the amide solvents, perhaps because of significant wall functionalization. AFM was used to study the filament diameter and length distributions in the final product, and interesting differences in these distributions were observed, depending on the chemical processing route.}, number={19}, journal={Journal of the American Chemical Society}, author={Furtado, CA and Kim, UJ and Gutierrez, HR and Pan, L and Dickey, EC and Eklund, PC}, year={2004}, pages={6095–6105} }
 @article{dickey_pan_lew_redwing_2004, title={Development of Doped and Heterostructured Si-Ge Nanowires}, volume={10}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S143192760488574X}, DOI={10.1017/S143192760488574X}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2004 in Savannah, Georgia, USA, August 1–5, 2004.}, number={S02}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Dickey, Elizabeth C. and Pan, Ling and Lew, Kok-Keong and Redwing, Joan M.}, year={2004}, month={Aug}, pages={22–23} }
 @article{yang_dickey_randall_2004, title={Failure Analysis of Ni-BaTiO3 Base-Metal Electrode Multilayer Ceramic Capacitors using Analytical Transmission Electron Microscopy}, volume={10}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927604885027}, DOI={10.1017/S1431927604885027}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2004 in Savannah, Georgia, USA, August 1–5, 2004.}, number={S02}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Yang, G. Y. and Dickey, E. C. and Randall, C. A.}, year={2004}, month={Aug}, pages={768–769} }
 @article{wang_lian_dickey_2004, title={Grain boundary segregation in yttrium-doped polycrystalline TiO2}, volume={52}, ISSN={1359-6454}, url={http://dx.doi.org/10.1016/j.actamat.2003.10.016}, DOI={10.1016/j.actamat.2003.10.016}, abstractNote={Grain boundary segregation of yttrium in titanium dioxide is studied systematically as a function of dopant concentration. Local grain boundary defect chemistry is quantitatively determined by analytical transmission electron microscopy and compared to equilibrium space-charge segregation models that incorporate both the electrostatic and elastic strain-energy driving forces for solute segregation. The thermodynamic models show that the elastic strain-energy driving force dominates in this system and that the electrostatic driving force contributes a 10–20% correction to the total solute segregation. In comparison to the experimental results, the theoretical models provide good predictions for several grain boundary parameters including local stoichiometry, solute interfacial excess and space-charge layer thickness.}, number={4}, journal={Acta Materialia}, publisher={Elsevier BV}, author={Wang, Qinglei and Lian, Guoda and Dickey, Elizabeth C.}, year={2004}, month={Feb}, pages={809–820} }
 @article{yang_dickey_randall_woodward_reaney_2004, title={HRTEM Study of a New Non-Stoichiometric BaTiO(3-δ) Structure}, volume={10}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927604884927}, DOI={10.1017/S1431927604884927}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2004 in Savannah, Georgia, USA, August 1–5, 2004.}, number={S02}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Yang, G. Y. and Dickey, E. C. and Randall, C. A. and Woodward, D. I. and Reaney, I. M.}, year={2004}, month={Aug}, pages={992–993} }
 @article{zhu_cammers-goodwin_zhao_dozier_dickey_2004, title={Kinetic precipitation of solution-phase polyoxomolybdate followed by transmission electron microscopy: A window to solution-phase nanostructure}, volume={10}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000221572900006&KeyUID=WOS:000221572900006}, DOI={10.1002/chem.200305468}, abstractNote={The structural nature of the polydisperse, nanoscopic components is elucidated both in the solution and the solid states of partially reduced polyoxomolybdate (see picture) derived from the {Mo132} keplerate, {(Mo)Mo5}12-{Mo2 acetate}30.}, number={10}, journal={Chemistry-a European Journal}, author={Zhu, Y and Cammers-Goodwin, A and Zhao, B and Dozier, A and Dickey, EC}, year={2004}, pages={2421–2427} }
 @article{deng_dickey_paderno_paderno_filippov_2004, title={Microstructure and Interface Characterization of Directionally Solidified LaB6-ZrB2 Eutectics}, volume={10}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927604885751}, DOI={10.1017/S1431927604885751}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2004 in Savannah, Georgia, USA, August 1–5, 2004.}, number={S02}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Deng, Hongqi and Dickey, Elizabeth C and Paderno, Youri and Paderno, Varvara and Filippov, Vladimir}, year={2004}, month={Aug}, pages={704–705} }
 @article{yang_lian_dickey_randall_barber_pinceloup_henderson_hill_beeson_skamser_2004, title={Oxygen nonstoichiometry and dielectric evolution of BaTiO3. Part II—insulation resistance degradation under applied dc bias}, volume={96}, ISSN={0021-8979 1089-7550}, url={http://dx.doi.org/10.1063/1.1809268}, DOI={10.1063/1.1809268}, abstractNote={The microchemical and microstructural origins of insulation-resistance degradation in BaTiO3-based capacitors are studied by complementary impedance spectroscopy and analytical transmission electron microscopy. The degradation under dc-field bias involves electromigration and accumulation of oxygen vacancies at interfaces. The nonstoichiometric BaTiO3−δ becomes locally more conducting through increased oxygen vacancy concentration and Ti ion reduction. The symmetry across the dielectric layer and locally across each grain is broken during the degradation process. Locally, the nonstoichiometry becomes so severe that metastable lattice structures are formed. The degradation in insulation resistance at the grain boundaries and electrode interfaces is associated with the double Schottky-barrier potential lowering and narrowing. This may correlate with an effective decrease in net acceptor charge density at the grain boundaries.}, number={12}, journal={Journal of Applied Physics}, publisher={AIP Publishing}, author={Yang, G. Y. and Lian, G. D. and Dickey, E. C. and Randall, C. A. and Barber, D. E. and Pinceloup, P. and Henderson, M. A. and Hill, R. A. and Beeson, J. J. and Skamser, D. J.}, year={2004}, month={Dec}, pages={7500–7508} }
 @article{yang_dickey_randall_barber_pinceloup_henderson_hill_beeson_skamser_2004, title={Oxygen nonstoichiometry and dielectric evolution of BaTiO3. Part I—improvement of insulation resistance with reoxidation}, volume={96}, ISSN={0021-8979 1089-7550}, url={http://dx.doi.org/10.1063/1.1809267}, DOI={10.1063/1.1809267}, abstractNote={Impedance spectroscopy, transmission electron microscopy, and electron energy-loss spectroscopy are used to correlate local electrical properties with the microstructure and microchemistry of BaTiO3 in Ni-electrode multilayer ceramic capacitors. High densities of linear defects and some grains with structural modulations are observed in BaTiO3 grains in the as-cofired capacitors. The modulated structure is formed on {111} planes of the BaTiO3. Both types of structural defects are associated with high concentrations of oxygen vacancies. In particular, the oxygen content in the BaTiO3 grains that are in direct contact with the internal Ni electrodes is less uniform with a systematic decrease in oxygen content towards the electrode. In the capacitors that are reoxidized in a higher oxygen partial pressure at lower temperature, the BaTiO3 grains are almost free of linear defects and structural modulations and the oxygen content is homogeneous throughout the BaTiO3 active layers. A concomitant improvement in the total insulation resistance is observed.}, number={12}, journal={Journal of Applied Physics}, publisher={AIP Publishing}, author={Yang, G. Y. and Dickey, E. C. and Randall, C. A. and Barber, D. E. and Pinceloup, P. and Henderson, M. A. and Hill, R. A. and Beeson, J. J. and Skamser, D. J.}, year={2004}, month={Dec}, pages={7492–7499} }
 @article{lew_pan_bogart_dilts_dickey_redwing_wang_cabassi_mayer_novak_2004, title={Structural and electrical properties of trimethylboron-doped silicon nanowires}, volume={85}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000224679300035&KeyUID=WOS:000224679300035}, DOI={10.1063/1.1792800}, abstractNote={Trimethylboron (TMB) was investigated as a p-type dopant source for the vapor–liquid–solid growth of boron-doped silicon nanowires (SiNWs). The boron concentration in the nanowires was measured using secondary ion mass spectrometry and results were compared for boron-doping using TMB and diborane (B2H6) sources. Boron concentrations ranging from 1×1018 to 4×1019cm−3 were obtained by varying the inlet dopant∕SiH4 gas ratio. TEM characterization revealed that the B2H6-doped SiNWs consisted of a crystalline core with a thick amorphous Si coating, while the TMB-doped SiNWs were predominantly single crystal even at high boron concentrations. The difference in structural properties was attributed to the higher thermal stability and reduced reactivity of TMB compared to B2H6. Four-point resistivity and gate-dependent conductance measurements were used to confirm p-type conductivity in the TMB-doped nanowires and to investigate the effect of dopant concentration on nanowire resistivity.}, number={15}, journal={Applied Physics Letters}, author={Lew, KK and Pan, L and Bogart, TE and Dilts, SM and Dickey, EC and Redwing, JM and Wang, YF and Cabassi, M and Mayer, TS and Novak, SW}, year={2004}, pages={3101–3103} }
 @inproceedings{redwing_lew_bogart_pan_dickey_carim_wang_cabassi_mayer_2004, title={Synthesis and properties of Si and SiGe/Si nanowires}, volume={5361}, url={https://app.dimensions.ai/details/publication/pub.1019339982}, DOI={10.1117/12.533572}, abstractNote={The fabrication of semiconductor nanowires, in which composition, size and conductivity can be controlled in both the radial and axial direction of the wire is of interest for fundamental studies of carrier confinement as well as nanoscale device development. In this study, group IV semiconductor nanowires, including Si, Ge and Si<sub>x</sub>Ge<sub>1-x</sub> alloy nanowires were fabricated by vapor-liquid-solid (VLS) growth using gaseous precursors. In the VLS process, gold is used to form a liquid alloy with Si and Ge which, upon supersaturation, precipitates a semiconductor nanowire. Nanoporous alumina membranes were used as templates for the VLS growth process, in order to control the diameter of the nanowires over the range from 45 nm to 200 nm. Intentional p-type and n-type doping was achieved through the addition of either trimethylboron, diborane or phosphine gas during nanowire growth. The electrical properties of undoped and intentionally doped silicon nanowires were characterized using field-assisted assembly to align and position the wires onto pre-patterned test bed structures. The depletion characteristics of back-gated nanowire structures were used to determine conductivity type and qualitatively compare dopant concentration. SiGe and SiGe/Si axial heterostructure nanowires were also prepared through the addition of germane gas during VLS growth. The Ge concentration in the wires was controllable over the range from 12 % to 25% by varying the inlet GeH<sub>4</sub>/SiH<sub>4</sub> ratio.}, booktitle={Proceedings of SPIE}, author={Redwing, JM and Lew, KK and Bogart, TE and Pan, L and Dickey, EC and Carim, AH and Wang, YF and Cabassi, MA and Mayer, TS}, year={2004}, pages={52–59} }
 @inbook{redwing_lew_bogart_pan_dickey_carim_wang_cabassi_mayer_2004, title={Synthesis and properties of Si and SiGe/Si nanowires}, volume={5361}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000222821000007&KeyUID=WOS:000222821000007}, booktitle={Quantum Dots, Nanoparticles, and Nanoclusters}, author={Redwing, JM and Lew, KK and Bogart, TE and Pan, L and Dickey, EC and Carim, AH and Wang, YF and Cabassi, MA and Mayer, TS}, year={2004}, pages={52–59} }
 @article{woodward_reaney_yang_dickey_randall_2004, title={Vacancy ordering in reduced barium titanate}, volume={84}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000221656900018&KeyUID=WOS:000221656900018}, DOI={10.1063/1.1759390}, abstractNote={A crystal structure is proposed for reduced barium titanate, BaTiO3−δ, δ≈0.33, formed during the degradation of Ni–BaTiO3 X7R multilayer ceramic capacitors. High-resolution transmission electron microscopy and selected-area electron diffraction have been used in combination with computer simulations to show that oxygen vacancies accrete on every third pseudocubic {111} plane, resulting in a cell with space group P3m1. Additionally, from electron energy loss spectroscopy, it is proposed that Ti4+ is reduced to Ti3+ as a mechanism of charge compensation within oxygen-deficient octahedra.}, number={23}, journal={Applied Physics Letters}, author={Woodward, DI and Reaney, IM and Yang, GY and Dickey, EC and Randall, CA}, year={2004}, pages={4650–4652} }
 @article{wang_dickey_lian_2004, title={Y and Nb Grain Boundary Segregation in Polycrystalline Titanium Dioxide}, volume={10}, ISSN={1431-9276 1435-8115}, url={http://dx.doi.org/10.1017/S1431927604885775}, DOI={10.1017/S1431927604885775}, abstractNote={Extended abstract of a paper presented at Microscopy and Microanalysis 2004 in Savannah, Georgia, USA, August 1–5, 2004.}, number={S02}, journal={Microscopy and Microanalysis}, publisher={Cambridge University Press (CUP)}, author={Wang, Qinglei and Dickey, E C and Lian, Guoda}, year={2004}, month={Aug}, pages={302–303} }
 @article{grimes_ong_varghese_yang_mor_paulose_dickey_ruan_pishko_kendig_et al._2003, title={A sentinel sensor network for hydrogen sensing}, volume={3}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000182273100003&KeyUID=WOS:000182273100003}, DOI={10.3390/s30300069}, abstractNote={A wireless sensor network is presented for in-situ monitoring of atmospheric hydrogen concentration. The hydrogen sensor network consists of multiple sensor nodes, equipped with titania nanotube hydrogen sensors, distributed throughout the area of interest; each node is both sensor, and data-relay station that enables extended wide area monitoring without a consequent increase of node power and thus node size. The hydrogen sensor is fabricated from a sheet of highly ordered titania nanotubes, made by anodization of a titanium thick film, to which platinum electrodes are connected. The electrical resistance of the hydrogen sensor varies from 245 Ω at 500 ppm hydrogen, to 10.23 kΩ at 0 ppm hydrogen (pure nitrogen environment). The measured resistance is converted to voltage, 0.049 V at 500 ppm to 2.046 V at 0 ppm, by interface circuitry. The microcontroller of the sensor node digitizes the voltage and transmits the digital information, using intermediate nodes as relays, to a host node that downloads measurement data to a computer for display. This paper describes the design and operation of the sensor network, the titania nanotube hydrogen sensors with an apparent low level resolution of approximately 0.05 ppm, and their integration in one widely useful device.}, number={3}, journal={Sensors}, author={Grimes, CA and Ong, KG and Varghese, OK and Yang, XP and Mor, G and Paulose, M and Dickey, EC and Ruan, CM and Pishko, MV and Kendig, JW and et al.}, year={2003}, pages={69–82} }
 @article{sinnott_dickey_2003, title={Ceramic/metal interface structures and their relationship to atomic- and meso-scale properties}, volume={43}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000188003000001&KeyUID=WOS:000188003000001}, DOI={10.1016/j.mser.2003.09.001}, abstractNote={Ceramic/metal interfaces have vast technological significance and are used in a variety of applications. This has prompted a concerted effort to develop fundamental structure/property relationships for these structures. This article critically reviews recent advances in complementary experimental and theoretical studies of ceramic/metal interfaces to provide an overview of progress made towards developing these relationships. In particular, the focus is on the structure, characterization, and modeling of non-reactive, bulk ceramic/metal interfaces. This includes determining interface atomic structure and chemistry and investigating impurity segregation to the interfaces. Additionally, the most important advances in the experimental and theoretical modeling of interfacial structure and chemistry are reviewed and comments are provided on the future outlook of this field.}, number={1-2}, journal={Materials Science & Engineering R-Reports}, author={Sinnott, SB and Dickey, EC}, year={2003}, pages={1–59} }
 @article{varghese_gong_paulose_grimes_dickey_2003, title={Crystallization and high-temperature structural stability of titanium oxide nanotube arrays}, volume={18}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000180363400022&KeyUID=WOS:000180363400022}, DOI={10.1557/JMR.2003.0022}, number={1}, journal={Journal of Materials Research}, author={Varghese, OK and Gong, DW and Paulose, M and Grimes, CA and Dickey, EC}, year={2003}, pages={156–165} }
 @inproceedings{sharma_sunkara_2003, title={Direct synthesis of silicon nanowires using silane and molten gallium}, volume={737}, booktitle={MRS Online Proceedings Library}, author={Sharma, S and Sunkara, MK}, year={2003}, pages={615–620} }
 @article{varghese_gong_paulose_ong_dickey_grimes_2003, title={Extreme changes in the electrical resistance of titania nanotubes with hydrogen exposure}, volume={15}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000182552300021&KeyUID=WOS:000182552300021}, DOI={10.1002/adma.200304586}, abstractNote={Extremely sensitive, drift-free, and robust hydrogen sensors based on titania nanotube arrays (see Figure) are reported. Very large changes in the electrical conductivity of the nanotubes upon exposure to hydrogen gas have been measured, over one order of magnitude greater than the previous record. Dependence of the electrical conductivity on both temperature and nanotube pore size is found.}, number={7-8}, journal={Advanced Materials}, author={Varghese, OK and Gong, DW and Paulose, M and Ong, KG and Dickey, EC and Grimes, CA}, year={2003}, pages={624–627} }
 @inbook{wang_lian_dickey_2003, title={Grain boundary segregation in titanium dioxide: Evaluation of relative driving forces for segregation}, volume={751}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000183444800030&KeyUID=WOS:000183444800030}, booktitle={Structure-Property Relationships of Oxide Surfaces and Interfaces Ii}, author={Wang, QL and Lian, GD and Dickey, EC}, year={2003}, pages={179–190} }
 @inproceedings{wang_lian_dickey_2003, title={Grain boundary segregation in titanium dioxide: Evaluation of relative driving forces for segregation}, volume={751}, booktitle={MRS Online Proceedings Library}, author={Wang, QL and Lian, GD and Dickey, EC}, year={2003}, pages={179–190} }
 @article{kovtyukhova_mallouk_pan_dickey_2003, title={Individual single-walled nanotubes and hydrogels made by oxidative exfoliation of carbon nanotube ropes}, volume={125}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000184654700051&KeyUID=WOS:000184654700051}, DOI={10.1021/ja0344516}, abstractNote={Single-walled carbon nanotubes were oxidized by a technique previously developed for the oxidation of graphite to graphite oxide (GO). This process involves treatment with concentrated H(2)SO(4) containing (NH(4))(2)S(2)O(8) and P(2)O(5), followed by H(2)SO(4) and KMnO(4). Oxidation results in complete exfoliation of nanotube ropes to yield individual oxidized tubes that are 40-500 nm long. The C:O:H atomic ratio of vacuum-dried oxidized nanotubes is approximately 2.7:1.0:1.2. XPS and IR spectra show evidence for surface O-H, C=O, and COOH groups. The oxidized nanotubes slowly form viscous hydrogels at unusually low concentration (>or=0.3 wt %), and this behavior is attributed to the formation of a hydrogen-bonded nanotube network. The oxidized tubes bind readily to amine-coated surfaces, on which they adsorb as smooth and dense monolayer films. Thin films of the oxidized nanotubes show ohmic current-voltage behavior, with resistivities in the range of 0.2-0.5 Omega-cm.}, number={32}, journal={Journal of the American Chemical Society}, author={Kovtyukhova, NI and Mallouk, TE and Pan, L and Dickey, EC}, year={2003}, pages={9761–9769} }
 @inproceedings{yang_dickey_randall_2003, title={Insights into degradation mechanisms and vacancy ordering in BaTiO <inf>3</inf>}, volume={9}, url={https://app.dimensions.ai/details/publication/pub.1113964956}, DOI={10.1017/s1431927603444255}, number={SUPPL. 2}, booktitle={Microscopy and Microanalysis}, author={Yang, GY and Dickey, EC and Randall, CA}, year={2003}, month={Jan}, pages={850–851} }
 @article{lian_dickey_chun_ku_samarth_2003, title={Interface structure and chemistry in ZnSe/Ga1-xMnxAs/ZnSe heterostructures}, volume={82}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000182993700024&KeyUID=WOS:000182993700024}, DOI={10.1063/1.1577825}, abstractNote={The structure and chemical composition of ZnSe/Ga1−xMnxAs/ZnSe multilayers grown on (100) GaAs substrates are investigated by high-resolution transmission electron microscopy imaging and spectroscopy techniques. While all layers grow epitaxially and the Ga1−xMnxAs layer is free of planar defects, a high density of stacking faults is observed in the ZnSe layer over Ga1−xMnxAs. The composition of the ferromagnetic layer is measured to be Ga0.93Mn0.07As, and the Mn valence was determined to be 2+. Compositional profiles across the interfaces quantified by electron energy-loss spectroscopy show that the ZnSe/Ga1−xMnxAs interfaces are wider than the ZnSe/GaAs–substrate interface, which is mainly attributed to interfacial roughness.}, number={21}, journal={Applied Physics Letters}, author={Lian, GD and Dickey, EC and Chun, SH and Ku, KC and Samarth, N}, year={2003}, pages={3656–3658} }
 @article{qian_andrews_jacques_kichambare_lian_dickey_2003, title={Low-temperature synthesis of large-area CNx nanotube arrays}, volume={3}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000183793100010&KeyUID=WOS:000183793100010}, DOI={10.1166/jnn.2003.159}, abstractNote={Well-aligned nitrogen-doped multiwall carbon nanotube arrays have been successfully grown over large areas on quartz and silicon wafers by floating-catalyst chemical vapor deposition at low temperatures (600 degrees C). These nitrogen-including nanotubes, derived from pyridine-ferrocene mixtures, have smaller outer diameters but larger inner diameters compared with carbon nanotubes grown from a xylene-ferrocene mixture under similar conditions. The N-doped nanotubes exhibit bamboo-like structures in the core. Elemental analysis and electron energy loss spectroscopy analysis show that the as-prepared nanotubes contain as much as 2.62 wt.% N, with most of the N concentrated in the inner few shells of the nanotube. Such large-scale arrays of well-aligned N-doped nanotubes on silicon wafers have a current density as high as 23.8 mA/cm2 at an applied electric field of 17 V/micron, which can be further improved by patterning the tubes and coating the silicon substrate with a conductive thin metal film for the fabrication of flat panel displays.}, number={1-2}, journal={Journal of Nanoscience and Nanotechnology}, author={Qian, DL and Andrews, R and Jacques, D and Kichambare, P and Lian, G and Dickey, EC}, year={2003}, pages={93–97} }
 @article{yang_dickey_randall_randall_mann_2003, title={Modulated and ordered defect structures in electrically degraded Ni-BaTiO3 multilayer ceramic capacitors}, volume={94}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000186138600081&KeyUID=WOS:000186138600081}, DOI={10.1063/1.1615300}, abstractNote={Structural defects formed on {111} planes of BaTiO3 during the degradation of high performance multilayer Ni–BaTiO3 X7R ceramic capacitors are studied using transmission electron microscopy and electron energy loss spectroscopy (EELS). Regular pseudocubic barium titanate grains are present in as-produced (virginal) base-metal electrode capacitors. However, there is a coexistence of regular, modulated, and long-range ordered structures in intentionally electrically degraded devices. The EELS analysis demonstrates that the concentration of oxygen vacancies in barium titanate with modulated or ordered structures is higher than that in the regular perovskite grains. The clustering or accumulation of oxygen vacancies in the structural framework of BaTiO3 gives rise to the formation of new metastable structures. These observations are consistent with earlier models for degradation, but demonstrate that the details of the process may be more complex than originally assumed. Here we introduce new details on the nature of the reduction process and the manner in which the lattice accommodates the enhanced oxygen vacancy concentration towards the failed regions of the capacitors and in the vicinity of the “blocking” cathodic electrodes.}, number={9}, journal={Journal of Applied Physics}, author={Yang, GY and Dickey, EC and Randall, CA and Randall, MS and Mann, LA}, year={2003}, pages={5990–5996} }
 @article{xiong_gupta_adu_dickey_lian_tham_fischer_eklund_2003, title={Raman spectroscopy and structure of crystalline gallium phosphide nanowires}, volume={3}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000185818800010&KeyUID=WOS:000185818800010}, DOI={10.1166/jnn.2003.208}, abstractNote={Gallium phosphide nanowires with a most probable diameter of approximately 20.0 nm and more than 10 microns in length have been synthesized by pulsed laser vaporization of a heated GaP/5% Au target. The morphology and microstructure of GaP nanowires have been investigated by scanning electron microscopy and transmission electron microscopy. Twins have been observed along the crystalline nanowires, which have a growth direction of [111]. Raman scattering shows a 4 cm-1 downshift of the longitudinal optical phonon peak in the nanowire with respect to the bulk; the transverse optical phonon frequency and line width are, however, the same as in the bulk. The quantum confinement model first proposed by Richter et al. cannot explain the observed behavior of the Raman modes.}, number={4}, journal={Journal of Nanoscience and Nanotechnology}, author={Xiong, QH and Gupta, R and Adu, KW and Dickey, EC and Lian, GD and Tham, D and Fischer, JE and Eklund, PC}, year={2003}, pages={335–339} }
 @article{lew_pan_dickey_redwing_2003, title={Vapor-liquid-solid growth of silicon-germanium nanowires}, volume={15}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000188051400008&KeyUID=WOS:000188051400008}, DOI={10.1002/adma200306035}, number={24}, journal={Advanced Materials}, author={Lew, KK and Pan, L and Dickey, EC and Redwing, JM}, year={2003}, pages={2073-+} }
 @article{lew_pan_dickey_redwing_2003, title={Vapor-liquid-solid growth of silicon-germanium nanowires}, volume={15}, url={https://app.dimensions.ai/details/publication/pub.1033138643}, DOI={10.1002/adma.200306035}, abstractNote={SiGe alloy nanowires (see Figure) have been fabricated using vapor–liquid–solid (VLS) growth with silane (SiH4) and germane (GeH4) gas sources. Growth conditions have been identified that produce nanowires with homogeneous alloy composition with negligible Ge coating on the wire surface. The Ge composition in the nanowire can be controlled by varying the inlet GeH4/(GeH4 + SiH4) gas ratio.}, number={24}, journal={Advanced Materials}, author={Lew, KK and Pan, L and Dickey, EC and Redwing, JM}, year={2003}, pages={2073-+} }
 @article{sharma_sunkara_2002, title={A non-traditional vapor-liquid-solid method for bulk synthesis of semiconductor nanowires}, volume={703}, journal={MRS Online Proceedings Library}, author={Sharma, S and Sunkara, MK}, year={2002}, pages={123–128} }
 @article{mao_sinnott_dickey_2002, title={Ab initio calculations of pristine and doped zirconia Sigma 5 (310)/[001] tilt grain boundaries}, volume={85}, url={https://app.dimensions.ai/details/publication/pub.1039542781}, DOI={10.1111/j.1151-2916.2002.tb00317.x}, abstractNote={The structure of the cubic-ZrO2 symmetrical tilt Σ5 (310)/[001] grain boundary is examined using density functional theory within the local density and pseudopotential approximations. Several pristine stoichiometric grain-boundary structures are investigated and compared with Z-contrast scanning transmission electron microscopy and electron energy loss spectroscopy results. The lowest-energy grain-boundary structure is found to agree well with the experimental data. When Y3+ is substituted for Zr4+ at various sites in the lowest-energy grain-boundary structure, the calculations indicate that Y3+ segregation to the grain boundary is energetically preferred to bulk doping, in agreement with experimental results.}, number={6}, journal={Journal of the American Ceramic Society}, author={Mao, ZG and Sinnott, SB and Dickey, EC}, year={2002}, pages={1594–1600} }
 @article{singh_grimes_dickey_2002, title={Fabrication of nanoporous TiO2 films through Benard-Marangoni convection}, volume={5}, url={https://app.dimensions.ai/details/publication/pub.1012750186}, DOI={10.1007/s10019-002-8643-5}, abstractNote={Fabrication of nanoporous TiO2 thin films through Benard-Marangoni convection is reported. Variation of pore size and morphology in the sol-gel deposited metal-oxide films is investigated as a function of ambient humidity and air flow velocity during film drying, sol concentration, and addition of water/acid to the sol.}, number={3-4}, journal={Materials Research Innovations}, author={Singh, RS and Grimes, CA and Dickey, EC}, year={2002}, pages={178–184} }
 @inproceedings{wang_lian_dickey_2002, title={Grain boundary segregation in titanium dioxide}, volume={8}, url={https://app.dimensions.ai/details/publication/pub.1113964252}, DOI={10.1017/s1431927602108026}, number={SUPPL. 2}, booktitle={Microscopy and Microanalysis}, author={Wang, Q and Lian, G and Dickey, EC}, year={2002}, month={Jan}, pages={1170–1171} }
 @article{varghese_gong_paulose_ong_grimes_dickey_2002, title={Highly ordered nanoporous alumina films: Effect of pore size and uniformity on sensing performance}, volume={17}, url={https://app.dimensions.ai/details/publication/pub.1022859229}, DOI={10.1557/JMR.2002.0172}, number={5}, journal={Journal of Materials Research}, author={Varghese, OK and Gong, DW and Paulose, M and Ong, KG and Grimes, CA and Dickey, EC}, year={2002}, pages={1162–1171} }
 @article{blondeau-patissier_lian_domenichini_steinbrunn_bourgeois_dickey_2002, title={Molybdenum thin-film growth on rutile titanium dioxide (110)}, volume={506}, url={https://app.dimensions.ai/details/publication/pub.1004871790}, DOI={10.1016/S0039-6028(02)01383-3}, abstractNote={Molybdenum films were deposited at room temperature on rutile TiO2(1 1 0) surfaces having different stoichiometries, surface roughnesses and crystallinities. The film structures and compositions and the substrate–film interfaces were investigated by X-ray diffraction, high-resolution transmission electron microscopy and energy-dispersive X-ray spectroscopy. Different substrate pretreatments resulted in markedly different film and interface structures. Under the growth conditions studied, no amorphous molybdenum oxide interlayers were formed upon deposition in contrast to previous studies. Preferred (1 1 0) textured Mo films grew on both air-annealed and oxygen-bombarded substrates. While sharp substrate–film interfaces were observed in the air-annealed samples, oxygen bombardment led to a rough interface. Epitaxial growth was achieved on argon-bombarded substrates, and a single crystal TiO interlayer was present as a result of the substrate pretreatment. The orientation relationship among three crystalline layers was: Mo(2 0 0)[0 0 1]//TiO(2 0 0)[0 1 1]//TiO2(1 1 0)[0 0 1]. Even though the growth was epitaxial, the argon bombardment resulted in a rough interface between the substrate and the TiO interlayer and between TiO and the Mo film. The results are compared with previous data on thin Mo film growth (⩽3 ML) on rutile TiO2(1 1 0), and the structural evolution is discussed.}, number={1-2}, journal={Surface Science}, author={Blondeau-Patissier, V and Lian, GD and Domenichini, B and Steinbrunn, A and Bourgeois, S and Dickey, EC}, year={2002}, pages={119–128} }
 @inproceedings{lian_dickey_ueno_sunkara_2002, title={Nanocrystalline diamond in Ru-doped DLC films}, volume={8}, url={https://app.dimensions.ai/details/publication/pub.1113963831}, DOI={10.1017/s1431927602103801}, number={SUPPL. 2}, booktitle={Microscopy and Microanalysis}, author={Lian, GD and Dickey, EC and Ueno, M and Sunkara, MK}, year={2002}, month={Jan}, pages={1146–1147} }
 @article{dickey_varghese_ong_gong_paulose_grimes_2002, title={Room temperature ammonia and humidity sensing using highly ordered nanoporous alumina films}, volume={2}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000182217000003&KeyUID=WOS:000182217000003}, DOI={10.3390/s20300091}, abstractNote={The effect of pore size and uniformity on the response of nanoporous alumina, formed on aluminum thick films through an anodization process, to ammonia and humidity at room temperature is reported. Pore sizes examined range from 13 nm to 48 nm, with pore size standard deviations ranging from 2.6 nm to 7.8 nm. The response of the material to ammonia and humidity is a strong function of pore size and operating frequency. At 5 kHz an alumina sensor with an average pore size of 13.6 nm, standard deviation 2.6 nm, exhibits a factor of two change in impedance magnitude as it is cycled between an ammonia and argon environment. At 5 kHz the same sensor exhibits a well-behaved change in impedance magnitude of 103 over 20% to 90% relative humidity. Cole-Cole plots of the 5 Hz to 13 MHz measured impedance spectra, modeled using equivalent circuits, are used to resolve the effects of adsorption and ion migration.}, number={3}, journal={Sensors}, author={Dickey, EC and Varghese, OK and Ong, KG and Gong, DW and Paulose, M and Grimes, CA}, year={2002}, pages={91–110} }
 @article{lian_dickey_ueno_sunkara_2002, title={Ru-doped nanostructured carbon films}, volume={11}, url={https://app.dimensions.ai/details/publication/pub.1046880742}, DOI={10.1016/S0925-9635(02)00165-6}, abstractNote={Pure and Ru-doped carbon films are deposited on Si (100) substrates by electron cyclotron resonance chemical vapor deposition. The films are characterized by transmission electron microscopy, electron energy loss spectroscopy, energy dispersive X-ray spectroscopy and atomic force microscopy. In both the pure and Ru-doped samples, diamond nanocrystallites are formed in amorphous carbon matrices. The Ru-doped film contains much smaller diamond nanocrystallites (approx. 3 nm) than the pure samples (approx. 11 nm). Lower surface roughnesses are observed in both pure and Ru-doped samples as compared to other reported nanocrystalline diamond films. The conductivity of the Ru-doped film is significantly higher than that of the pure film. The results show that Ru-doped nanocrystalline diamond films have unique structures and properties as compared to pure nanocrystalline diamond films or metal doped diamond-like carbon films, which may offer advantages for electrochemical, optical-window, field emission or tribological applications.}, number={12}, journal={Diamond and Related Materials}, author={Lian, GD and Dickey, EC and Ueno, M and Sunkara, MK}, year={2002}, pages={1890–1896} }
 @article{paulose_grimes_varghese_dickey_2002, title={Self-assembled fabrication of aluminum-silicon nanowire networks}, volume={81}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000176426000052&KeyUID=WOS:000176426000052}, DOI={10.1063/1.1492005}, abstractNote={Uniquely structured two-dimensional aluminum–silicon alloy nanowire networks are fabricated on glass and silicon substrates by dealloying an aluminum–silicon thin film through selective chemical etching. The nanowire network is comprised of 3–6 nm diameter wires with lengths of 50–200 nm, and a wire density of approximately 1010 wires/cm2. The spatial extent of the fabricated nanowire network is limited only by the substrate dimensions. Current–voltage measurements reveal the metallic nature of the nanowires, with current propagating throughout the nanowire network. The fabrication route offers the possibility for achieving billion wire/cm2 devices as a relatively low cost production commodity.}, number={1}, journal={Applied Physics Letters}, author={Paulose, M and Grimes, CA and Varghese, OK and Dickey, EC}, year={2002}, pages={153–155} }
 @inproceedings{lian_dickey_chun_samarth_2002, title={Structure characterization of ZnSe/GaMnAs quantum well on GaAs substrate}, volume={8}, url={https://app.dimensions.ai/details/publication/pub.1113963918}, DOI={10.1017/s1431927602104685}, number={SUPPL. 2}, booktitle={Microscopy and Microanalysis}, author={Lian, G and Dickey, E and Chun, SH and Samarth, N}, year={2002}, month={Jan}, pages={1620–1621} }
 @article{kichambare_qian_dickey_grimes_2002, title={Thin film metallic catalyst coatings for the growth of multiwalled carbon nanotubes by pyrolysis of xylene}, volume={40}, url={https://app.dimensions.ai/details/publication/pub.1022963183}, DOI={10.1016/S0008-6223(02)00033-7}, abstractNote={Thin film metallic coatings applied to alumina and silicon substrates are investigated for their use as a catalyst to help grow high-quality multiwall carbon nanotubes (MWNTs). Substrate coatings examined include Fe, Tb:Fe, Ni, Cu, and Ni:Fe, with xylene used as the hydrocarbon source. Coating the substrate with Tb90Fe10 and Ni80Fe20 facilitated dense and uniform growth of MWNTs without graphitic particles; Ni and Fe substrate coatings produced graphitic particles in addition to the MWNTs, while Tb and Cu were found to be completely inactive with no MWNT growth. Many of the MWNTs grown over Ni:Fe have a helical appearance, while the MWNTs grown over Tb90Fe10 did not contain catalyst particles}, number={11}, journal={Carbon}, author={Kichambare, PD and Qian, D and Dickey, EC and Grimes, CA}, year={2002}, pages={1903–1909} }
 @inproceedings{sharma_sunkara_miranda_lian_dickey_2001, title={A novel low temperature synthesis method for semiconductor nanowires}, volume={676}, DOI={10.1557/proc-676-y1.6}, booktitle={MRS Online Proceedings Library}, author={Sharma, S and Sunkara, MK and Miranda, R and Lian, G and Dickey, EC}, year={2001}, month={Jan} }
 @inbook{dickey_fan_yong_sinnott_pennycook_2001, title={Atomic scale analysis of cubic zirconia grain boundaries}, volume={589}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000172649100048&KeyUID=WOS:000172649100048}, booktitle={Advances in Materials Problem Solving With the Electron Microscope}, author={Dickey, EC and Fan, X and Yong, M and Sinnott, SB and Pennycook, SJ}, year={2001}, pages={323–328} }
 @article{dickey_fan_yong_sinnott_pennycook_2001, title={Atomic scale analysis of cubic zirconia grain boundaries}, volume={589}, journal={MRS Online Proceedings Library}, author={Dickey, EC and Fan, X and Yong, M and Sinnott, SB and Pennycook, SJ}, year={2001}, pages={323–328} }
 @article{sunkara_sharma_miranda_lian_dickey_2001, title={Bulk synthesis of silicon nanowires using a low-temperature vapor-liquid-solid method}, volume={79}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000170647200046&KeyUID=WOS:000170647200046}, DOI={10.1063/1.1401089}, abstractNote={Silicon nanowires will find applications in nanoscale electronics and optoelectronics both as active and passive components. Here, we demonstrate a low-temperature vapor–liquid–solid synthesis method that uses liquid-metal solvents with low solubility for silicon and other elemental semiconductor materials. This method eliminates the usual requirement of quantum-sized droplets in order to obtain quantum-scale one-dimensional structures. Specifically, we synthesized silicon nanowires with uniform diameters distributed around 6 nm using gallium as the molten solvent, at temperatures less than 400 °C in hydrogen plasma. The potential exists for bulk synthesis of silicon nanowires at temperatures significantly lower than 400 °C. Gallium forms a eutectic with silicon near room temperature and offers a wide temperature range for bulk synthesis of nanowires. These properties are important for creating monodispersed one-dimensional structures capable of yielding sharp hetero- or homointerfaces.}, number={10}, journal={Applied Physics Letters}, author={Sunkara, MK and Sharma, S and Miranda, R and Lian, G and Dickey, EC}, year={2001}, pages={1546–1548} }
 @article{frazer_dickey_sayir_2001, title={Crystallographic texture and orientation variants in Al2O3-Y3Al5O12 directionally solidified eutectic crystals}, volume={233}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000170986400026&KeyUID=WOS:000170986400026}, DOI={10.1016/S0022-0248(01)01590-1}, abstractNote={Eutectic rods of Al2O3 and Y3Al5O12 were grown by a laser-heated float zone method, and their microstructure and crystallographic texture were studied by scanning electron microscopy, electron backscattered diffraction and x-ray diffraction. The composites were found to be highly textured with two twin-related crystallographic orientation relationships between the phases. Electron backscattered diffraction was employed to determine the spatial distribution of the orientational variants within the samples and to define the crystallographic orientation of various microstructural features.}, number={1-2}, journal={Journal of Crystal Growth}, author={Frazer, CS and Dickey, EC and Sayir, A}, year={2001}, pages={187–195} }
 @article{grimes_dickey_mungle_ong_qian_2001, title={Effect of purification of the electrical conductivity and complex permittivity of multiwall carbon nanotubes}, volume={90}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000171562100067&KeyUID=WOS:000171562100067}, DOI={10.1063/1.1400100}, abstractNote={In this work we report on the complex permittivity spectra and electrical conductivity of both as-fabricated and graphitized multiwall carbon nanotubes (MWNTs). The high-temperature annealing removes the Fe3C catalyst particles present in the as-fabricated material, enabling the intrinsic MWNT properties to be measured. The permittivity spectra of 1 wt % MWNT-polystyrene composite films are measured from 75 to 1875 MHz. Comparison of measurements with an appropriate effective medium model shows that the residual catalyst inclusions in the core of the nanotube increase the average electrical conductivity by approximately a factor of 3.5.}, number={8}, journal={Journal of Applied Physics}, author={Grimes, CA and Dickey, EC and Mungle, C and Ong, KG and Qian, D}, year={2001}, pages={4134–4137} }
 @article{varghese_kichambre_gong_ong_dickey_grimes_2001, title={Gas sensing characteristics of multi-wall carbon nanotubes}, volume={81}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000172710900005&KeyUID=WOS:000172710900005}, DOI={10.1016/S0925-4005(01)00923-6}, abstractNote={Impedance spectroscopy was used to study the gas sensing behavior of both capacitance and resistance based sensors employing multi-wall carbon nanotubes (MWNTs) as the active sensing element. Studies revealed the chemisorption of reducing gases upon the surface of the MWNTs. Increasing sensor impedance was observed with increasing humidity or partial pressures of ammonia, carbon monoxide, and carbon dioxide. The impedance changes are attributed to p-type conductivity in semiconducting MWNTs, and the formation of Schottky barriers between the metallic and semiconducting nanotubes. Reversible behavior is demonstrated for the MWNT sensors in response to humidity, carbon monoxide and carbon dioxide. The MWNT sensors strongly respond to ammonia behaving as dosimeters.}, number={1}, journal={Sensors and Actuators B-Chemical}, author={Varghese, OK and Kichambre, PD and Gong, D and Ong, KG and Dickey, EC and Grimes, CA}, year={2001}, pages={32–41} }
 @article{qian_dickey_2001, title={In-situ transmission electron microscopy studies of polymer-carbon nanotube composite deformation}, volume={204}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000171285700005&KeyUID=WOS:000171285700005}, DOI={10.1046/j.1365-2818.2001.00940.x}, abstractNote={This paper demonstrates the viability of in-situ transmission electron microscopy for studying the deformation mechanisms of polymer nano-composites. In-situ straining studies are performed on carbon multiwalled nanotube (MWNT)-polystyrene composite films. The experiments show that load transfer across the nanotube-polystyrene interface is operative well into the plastic deformation regime of the composite film. The MWNTs are observed to bridge cracks propagating through the polystyrene, providing closure stresses across the crack wake. Although some MWNTs fracture by either a sword-in-sheath mechanism or transverse shear fracture, most of the MWNTs eventually debond at the MWNT-polymer interface and subsequently pull out of the matrix.}, journal={Journal of Microscopy-Oxford}, author={Qian, D and Dickey, EC}, year={2001}, pages={39–45} }
 @inbook{frazer_jones_dickey_2001, title={Interfacial compatibility stresses in alumina-zirconia and alumina-YAG composites}, volume={124}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000171046100029&KeyUID=WOS:000171046100029}, booktitle={Advances in Ceramic Matrix Composites Vi}, author={Frazer, CS and Jones, CE and Dickey, EC}, year={2001}, pages={339–350} }
 @inproceedings{frazer_jones_dickey_2001, title={Interfacial compatibility stresses in alumina-zirconia and alumina-YAG composites}, volume={124}, booktitle={Ceramic Transactions}, author={Frazer, CS and Jones, CE and Dickey, EC}, year={2001}, pages={339–350} }
 @book{mrvos_patil_dickey_wonderly_2001, title={Measurement of modulus changes of a phenolic adhesive using nanoindentation for an inkjet printhead nozzle plate}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000183952700086&KeyUID=WOS:000183952700086}, journal={Is&t's Nip17: International Conference on Digital Printing Technologies}, author={Mrvos, JM and Patil, GS and Dickey, EC and Wonderly, CT}, year={2001}, pages={385–391} }
 @inproceedings{mrvos_patil_dickey_wonderly_2001, title={Measurement of modulus changes of a phenolic adhesive using nanoindentation for an inkjet printhead nozzle plate}, booktitle={International Conference on Digital Printing Technologies}, author={Mrvos, JM and Patil, GS and Dickey, EC and Wonderly, CT}, year={2001}, pages={385–391} }
 @article{grimes_singh_dickey_varghese_2001, title={Metal-oxide films with magnetically-modulated nanoporous architectures}, volume={16}, url={https://app.dimensions.ai/details/publication/pub.1027854055}, DOI={10.1557/JMR.2001.0234}, number={6}, journal={Journal of Materials Research}, author={Grimes, CA and Singh, RS and Dickey, EC and Varghese, OK}, year={2001}, pages={1686–1693} }
 @inproceedings{grimes_singh_dickey_varghese_2001, title={Metal-oxide films with magnetically-modulated nanoporous architectures}, volume={4468}, url={https://app.dimensions.ai/details/publication/pub.1048154383}, DOI={10.1117/12.452555}, abstractNote={A magnetically-driven method for controlling nano- dimensional porosity in sol gel derived metal oxide films, including TiO<SUB>2</SUB>, Al<SUB>2</SUB>O<SUB>3</SUB>, and SnO<SUB>2</SUB>, coated onto ferromagnetic amorphous substrates, such as the magnetically-soft Metglas alloys, is described. Based on the porous structures observed dependence on external magnetic field, a model is suggested to explain the phenomena. Under well-defined conditions it appears that the sol particles coming out of solution, and undergoing Brownian motion, follow the magnetic field lines oriented perpendicularly to the substrate surface associated with the magnetic domain walls of the substrate; hence the porosity developed during solvent evaporation correlates with the magnetic domain size.}, booktitle={Proceedings of SPIE}, author={Grimes, CA and Singh, RS and Dickey, EC and Varghese, OK}, year={2001}, pages={8–16} }
 @article{guo_warschkow_ellis_dravid_dickey_2001, title={Oxide-oxide interfaces: Atomistic and density functional study of cubic-ZrO2(100)vertical bar vertical bar NiO(111)}, volume={84}, url={https://app.dimensions.ai/details/publication/pub.1038119010}, DOI={10.1111/j.1151-2916.2001.tb01070.x}, abstractNote={The cubic-ZrO2 (100) ‖ NiO (111) interface provides an opportunity for comparison between atomic-scale measurements, atomistic simulations, and theoretical electronic structures. High-resolution electron microscopy indicates that the oxides share a common oxygen layer and that the small lattice strain is largely taken up by NiO near the interface. Using simple Coulomb plus Buckingham-type interatomic potentials, we are able to provide a more focused picture, revealing two types of boundary. The lowest energy interface is highly planar, almost ideal in structure; there is a second interface, of higher energy, that shows a rumpled structure with strain taken up by deformation of nickel chains. Depth profiling of atomic site energies permits calculation of interface versus bulk and surface energies, and it shows that the interface effects penetrate only two to three atomic layers. Embedded cluster density functional studies of bulk and interface-region sites permit the characterization of perturbations of electronic density around the boundaries.}, number={11}, journal={Journal of the American Ceramic Society}, author={Guo, CX and Warschkow, O and Ellis, DE and Dravid, VP and Dickey, EC}, year={2001}, pages={2677–2684} }
 @article{dickey_ma_bagiyono_lian_sinnott_wagner_2001, title={Preferred crystallographic orientation relationships of nickel films deposited on (100) cubic-zirconia substrates (vol 372, pg 37, 2000)}, volume={384}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000167437800026&KeyUID=WOS:000167437800026}, DOI={10.1016/S0040-6090(01)00801-X}, number={2}, journal={Thin Solid Films}, author={Dickey, EC and Ma, Y and Bagiyono and Lian, GD and Sinnott, SB and Wagner, T}, year={2001}, pages={307} }
 @article{andrews_jacques_qian_dickey_2001, title={Purification and structural annealing of multiwalled carbon nanotubes at graphitization temperatures}, volume={39}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000170525000008&KeyUID=WOS:000170525000008}, DOI={10.1016/S0008-6223(00)00301-8}, abstractNote={In this work, we present a systematic study of the effects of graphitization on the structural perfection of multiwalled carbon nanotubes. High purity nanotubes were produced by a low temperature CVD method and subsequently annealed at temperatures between 1600 and 3000°C. The nanotubes were characterized for chemical purity, interlayer spacing, and defect healing. The graphitization procedure was found to remove residual metal catalyst in the nanotubes and reduce the wall defects as reflected in a reduced interlayer spacing between the graphene shells. Graphitization presents a low-cost, commercially viable method of purifying and ordering multiwall carbon nanotubes.}, number={11}, journal={Carbon}, author={Andrews, R and Jacques, D and Qian, D and Dickey, EC}, year={2001}, pages={1681–1687} }
 @article{dickey_fan_pennycook_2001, title={Structure and chemistry of yttria-stabilized cubic-zirconia symmetric tilt grain boundaries}, volume={84}, url={https://app.dimensions.ai/details/publication/pub.1025892814}, DOI={10.1111/j.1151-2916.2001.tb00842.x}, abstractNote={The atomic structures of two symmetric [001] tilt grain boundaries in yttria-stabilized cubic-zirconia, Σ5 (310) and near-Σ13 (510), are studied by Z-contrast scanning transmission electron microscopy. Both boundaries are composed of periodic arrays of highly symmetric structural units, with a distinct unit for each boundary. Oxygen K-edge electron energy-loss spectra show that the oxygen coordination is similar between the bulk and grain boundary, indicating that oxygen ions within the grain boundary reside in distorted tetrahedral sites. Atomic models of the grain boundaries are proposed that are consistent with the experimental data. The core structures are different from previously studied metal or oxide grain boundaries and are unique to the fluorite structure. Yttrium segregation to the grain boundaries is also investigated by electron energy-loss spectroscopy. Yttrium is found to segregate preferentially to the Σ5 grain boundary, and the spatial distribution of the segregation layer is confined to within 1 nm of the boundary plane.}, number={6}, journal={Journal of the American Ceramic Society}, author={Dickey, EC and Fan, XD and Pennycook, SJ}, year={2001}, pages={1361–1368} }
 @article{gong_grimes_varghese_hu_singh_chen_dickey_2001, title={Titanium oxide nanotube arrays prepared by anodic oxidation}, volume={16}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000172585100001&KeyUID=WOS:000172585100001}, DOI={10.1557/JMR.2001.0457}, number={12}, journal={Journal of Materials Research}, author={Gong, D and Grimes, CA and Varghese, OK and Hu, WC and Singh, RS and Chen, Z and Dickey, EC}, year={2001}, pages={3331–3334} }
 @article{cammers-goodwin_zhao_chowdhury_dickey_2001, title={Viral-like self assembly, from design and synthesis to microscopy.}, volume={221}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000168824800657&KeyUID=WOS:000168824800657}, journal={Abstracts of Papers of the American Chemical Society}, author={Cammers-Goodwin, A and Zhao, B and Chowdhury, C and Dickey, EC}, year={2001}, pages={U111} }
 @inproceedings{cammers-goodwin_zhao_chowdhury_dickey_2001, title={Viral-like self assembly, from design and synthesis to microscopy.}, volume={221}, booktitle={ACS National Meeting Book of Abstracts}, author={Cammers-Goodwin, A and Zhao, B and Chowdhury, C and Dickey, EC}, year={2001}, pages={U111–U111} }
 @article{dickey_grimes_jain_ong_qian_kichambare_andrews_jacques_2001, title={Visible photoluminescence from ruthenium-doped multiwall carbon nanotubes}, volume={79}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000172489100039&KeyUID=WOS:000172489100039}, DOI={10.1063/1.1419238}, abstractNote={Visible photoluminescence at 515 nm of ruthenium-doped multiwall carbon nanotubes, fabricated on quartz substrates using a chemical vapor deposition technique, is reported. The well-aligned nanotubes serve as templates for the luminescent, residual ruthenium–iron catalyst particles contained within the nanotubes, restricting the particle size to about 10 nm. The synthesis technique can be readily extended to other luminescent dopants; moreover, since nanotube arrays can be readily grown from patterned substrates, nanotube-based optoelectronic devices may be achieved.}, number={24}, journal={Applied Physics Letters}, author={Dickey, EC and Grimes, CA and Jain, MK and Ong, KG and Qian, D and Kichambare, PD and Andrews, R and Jacques, D}, year={2001}, pages={4022–4024} }
 @article{fan_dickey_eklund_williams_grigorian_buczko_pantelides_pennycook_2000, title={Atomic Arrangement of Iodine Atoms inside Single-Walled Carbon Nanotubes}, volume={84}, ISSN={0031-9007 1079-7114}, url={http://dx.doi.org/10.1103/PhysRevLett.84.4621}, DOI={10.1103/PhysRevLett.84.4621}, abstractNote={We report atomic resolution Z-contrast scanning transmission electron microscopy images that reveal the incorporation of I atoms in the form of helical chains inside single-walled carbon nanotubes. Density functional calculations and topological considerations provide a consistent interpretation of the experimental data. Charge transfer between the nanotube walls and the I chains is associated with the intercalation.}, number={20}, journal={Physical Review Letters}, publisher={American Physical Society (APS)}, author={Fan, X. and Dickey, E. C. and Eklund, P. C. and Williams, K. A. and Grigorian, L. and Buczko, R. and Pantelides, S. T. and Pennycook, S. J.}, year={2000}, month={May}, pages={4621–4624} }
 @inbook{sunkara_koduri_dickey_fan_2000, title={Behavior of redox reactions on metal-doped diamondlike carbon films}, volume={99}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000089239900050&KeyUID=WOS:000089239900050}, booktitle={Diamond Materials Vi}, author={Sunkara, MK and Koduri, P and Dickey, EC and Fan, X}, year={2000}, pages={448–457} }
 @inproceedings{sunkara_koduri_dickey_fan_2000, title={Behavior of redox reactions on metal-doped diamondlike carbon films}, volume={99}, number={32}, booktitle={DIAMOND MATERIALS VI}, author={Sunkara, MK and Koduri, P and Dickey, EC and Fan, X}, year={2000}, pages={448–457} }
 @inbook{fan_dickey_eklund_williams_grigorian_puretzky_geohegan_buczko_pantelides_pennycook_2000, title={Direct observation of intercalant and catalyst particle in single wall carbon nanotubes}, volume={593}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000089239300020&KeyUID=WOS:000089239300020}, booktitle={Amorphous and Nanostructured Carbon}, author={Fan, X and Dickey, EC and Eklund, P and Williams, K and Grigorian, L and Puretzky, A and Geohegan, D and Buczko, R and Pantelides, ST and Pennycook, SJ}, year={2000}, pages={129–134} }
 @inproceedings{fan_dickey_eklund_williams_grigorian_puretzky_geohegan_buczko_pantelides_pennycook_2000, title={Direct observation of intercalant and catalyst particle in single wall carbon nanotubes}, volume={593}, booktitle={MRS Online Proceedings Library}, author={Fan, X and Dickey, EC and Eklund, P and Williams, K and Grigorian, L and Puretzky, A and Geohegan, D and Buczko, R and Pantelides, ST and Pennycook, SJ}, year={2000}, pages={129–134} }
 @article{grimes_qian_dickey_allen_eklund_2000, title={Laser pyrolysis fabrication of ferromagnetic gamma(')-Fe4N and FeC nanoparticles}, volume={87}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000086727200314&KeyUID=WOS:000086727200314}, DOI={10.1063/1.373419}, abstractNote={Using the laser pyrolysis method, single phase gamma'-Fe4N nanoparticles were prepared by a two step method involving preparation of nanoscale iron oxide and a subsequent gas-solid nitridation reaction. Single phase Fe3C and Fe7C3 could be prepared by laser pyrolysis from Fe(CO)5 and 3C2H4 directly. Characterization techniques such as XRD, TEM and vibrating sample magnetometer were used to measure phase structure, particle size and magnetic properties of these nanoscale nitride and carbide particles.}, number={9}, journal={Journal of Applied Physics}, author={Grimes, CA and Qian, D and Dickey, EC and Allen, JL and Eklund, PC}, year={2000}, pages={5642–5644} }
 @article{qian_dickey_andrews_rantell_2000, title={Load transfer and deformation mechanisms in carbon nanotube-polystyrene composites}, volume={76}, ISSN={0003-6951 1077-3118}, url={http://dx.doi.org/10.1063/1.126500}, DOI={10.1063/1.126500}, abstractNote={Multiwall carbon nanotubes have been dispersed homogeneously throughout polystyrene matrices by a simple solution-evaporation method without destroying the integrity of the nanotubes. Tensile tests on composite films show that 1 wt % nanotube additions result in 36%–42% and ∼25% increases in elastic modulus and break stress, respectively, indicating significant load transfer across the nanotube-matrix interface. In situ transmission electron microscopy studies provided information regarding composite deformation mechanisms and interfacial bonding between the multiwall nanotubes and polymer matrix.}, number={20}, journal={Applied Physics Letters}, publisher={AIP Publishing}, author={Qian, D. and Dickey, E. C. and Andrews, R. and Rantell, T.}, year={2000}, month={May}, pages={2868–2870} }
 @article{grimes_kouzoudis_dickey_qian_anderson_shahidain_lindsey_green_2000, title={Magnetoelastic sensors in combination with nanometer-scale honeycombed thin film ceramic TiO2 for remote query measurement of humidity}, volume={87}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000086727200224&KeyUID=WOS:000086727200224}, DOI={10.1063/1.373341}, abstractNote={Ribbonlike magnetoelastic sensors can be considered the magnetic analog of an acoustic bell; in response to an externally applied magnetic field impulse the sensors emit magnetic flux with a characteristic resonant frequency. The magnetic flux can be detected external to the test area using a pick-up coil, enabling query remote monitoring of the sensor. The characteristic resonant frequency of a magnetoelastic sensor changes in response to mass loads. [L.D. Landau and E. M. Lifshitz, Theory of Elasticity, 3rd ed. (Pergamon, New York, 1986). p. 100].Therefore, remote query chemical sensors can be fabricated by combining the magnetoelastic sensors with a mass changing, chemically responsive layer. In this work magnetoelastic sensors are coated with humidity-sensitive thin films of ceramic, nanodimensionally porous TiO2 to make remote query humidity sensors.}, number={9}, journal={Journal of Applied Physics}, author={Grimes, CA and Kouzoudis, D and Dickey, EC and Qian, D and Anderson, MA and Shahidain, R and Lindsey, M and Green, L}, year={2000}, pages={5341–5343} }
 @article{dickey_bagiyono_lian_sinnott_wagner_2000, title={Preferred crystallographic orientation relationships of nickel films deposited on (100) cubic-zirconia substrates}, volume={372}, ISSN={0040-6090}, url={http://dx.doi.org/10.1016/s0040-6090(00)01052-x}, DOI={10.1016/s0040-6090(00)01052-x}, abstractNote={Preferred crystallographic orientation relationships between nickel films grown on (100) cubic-zirconia substrates were studied by a variety of electron diffraction techniques. The predominant orientation relationship found was Ni (111)//ZrO2 (100); Ni 〈1̄10〉//ZrO2 [010], while a secondary cube-on-cube orientation relationship was also observed. Orientation imaging microscopy (OIM) shows the different orientations to be distributed homogeneously across the substrate. The near coincident site lattice (NCSL) theory was employed to rationalize the observed orientation relationships from a geometrical perspective. The experimentally observed orientations do lead to small NCSL unit cells, but not always the smallest possible. It is also found that the choice of sublattice for calculating the NCSL is significant in this system, since the Zr and O sublattices of cubic-zirconia have different atomic spacings and coordination.}, number={1-2}, journal={Thin Solid Films}, publisher={Elsevier BV}, author={Dickey, E.C. and Bagiyono, Y.Maa and Lian, G.D. and Sinnott, S.B. and Wagner, T.}, year={2000}, month={Sep}, pages={37–44} }
 @inbook{fan_dickey_pennycook_2000, title={Study of chromium-doped diamond-like carbon by Z-contrast imaging and electron energy loss spectroscopy}, volume={593}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000089239300051&KeyUID=WOS:000089239300051}, booktitle={Amorphous and Nanostructured Carbon}, author={Fan, X and Dickey, EC and Pennycook, SJ}, year={2000}, pages={329–334} }
 @inproceedings{fan_dickey_pennycook_2000, title={Study of chromium-doped diamond-like carbon by Z-contrast imaging and electron energy loss spectroscopy}, volume={593}, booktitle={MRS Online Proceedings Library}, author={Fan, X and Dickey, EC and Pennycook, SJ}, year={2000}, pages={329–334} }
 @inbook{jacques_villain_rao_andrews_derbyshire_dickey_qian_2000, title={Synthesis of multiwalled carbon nanotubes}, volume={593}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000089239300002&KeyUID=WOS:000089239300002}, booktitle={Amorphous and Nanostructured Carbon}, author={Jacques, D and Villain, S and Rao, AM and Andrews, R and Derbyshire, F and Dickey, EC and Qian, DL}, year={2000}, pages={15–20} }
 @inproceedings{jacques_villain_rao_andrews_derbyshire_dickey_qian_2000, title={Synthesis of multiwalled carbon nanotubes}, volume={593}, booktitle={MRS Online Proceedings Library}, author={Jacques, D and Villain, S and Rao, AM and Andrews, R and Derbyshire, F and Dickey, EC and Qian, DL}, year={2000}, pages={15–20} }
 @book{dickey_pint_alexander_wright_2000, title={The effect of platinum on the growth and adhesion of alpha-Al2O3 scales}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000165895100010&KeyUID=WOS:000165895100010}, journal={High Temperature Surface Engineering}, author={Dickey, EC and Pint, BA and Alexander, KB and Wright, IG}, year={2000}, pages={115–128} }
 @inproceedings{dickey_pint_alexander_wright_2000, title={The effect of platinum on the growth and adhesion of alpha-Al2O3 scales}, booktitle={HIGH TEMPERATURE SURFACE ENGINEERING}, author={Dickey, EC and Pint, BA and Alexander, KB and Wright, IG}, year={2000}, pages={115–128} }
 @article{pennycook_dickey_nellist_chisholm_yan_pantelides_1999, title={A combined experimental and theoretical approach to atomic structure and segregation at ceramic interfaces}, volume={19}, url={https://app.dimensions.ai/details/publication/pub.1044231159}, DOI={10.1016/S0955-2219(99)00126-0}, abstractNote={Abstract In the last few years, the scanning transmission electron microscope has become capable of forming electron probes of atomic dimensions. This makes possible the technique of Z-contrast imaging, a method of forming direct images at atomic resolution with high compositional sensitivity. Atomic column positions can be determined to high accuracy from the image, and columns containing high-Z impurities will be visible. Atomic resolution electron energy loss spectroscopy is possible by locating the probe over particular atomic columns or planes seen in the image. This provides complementary information on low-Z species and chemical bonding. Such data represents an ideal starting point for first-principles theoretical calculations of energetics and dynamics, avoiding time-consuming searches of trial structures. Examples are shown of ordering in relaxor ferroelectrics, interfacial termination in oxide–oxide and metal–oxide interfaces, and an impurity-induced structural transformation of a ceramic grain boundary.}, number={13-14}, journal={Journal of the European Ceramic Society}, author={Pennycook, SJ and Dickey, EC and Nellist, PD and Chisholm, MF and Yan, Y and Pantelides, ST}, year={1999}, pages={2211–2216} }
 @article{andrews_jacques_rao_derbyshire_qian_fan_dickey_chen_1999, title={Continuous production of aligned carbon nanotubes: a step closer to commercial realization}, volume={303}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000079955900003&KeyUID=WOS:000079955900003}, DOI={10.1016/S0009-2614(99)00282-1}, abstractNote={High-purity aligned multi-walled carbon nanotubes (MWNTs) were synthesized through the catalytic decomposition of a ferrocene–xylene mixture at ∼675°C in a quartz tube reactor and over quartz substrates, with a conversion of ∼25% of the total hydrocarbon feedstock. Under the experimental conditions used, scanning electron microscope images reveal that the MWNT array grows perpendicular to the quartz substrates at an average growth rate of ∼25 μm/h. A process of this nature which does not require preformed substrates, and which operates at atmospheric pressure and moderate temperatures, could be scaled up for continuous or semi-continuous production of MWNTs.}, number={5-6}, journal={Chemical Physics Letters}, author={Andrews, R and Jacques, D and Rao, AM and Derbyshire, F and Qian, D and Fan, X and Dickey, EC and Chen, J}, year={1999}, pages={467–474} }
 @article{dickey_fan_pennycock_1999, title={Direct atomic-scale imaging of ceramic interfaces}, volume={47}, url={https://app.dimensions.ai/details/publication/pub.1022872591}, DOI={10.1016/S1359-6454(99)00266-9}, abstractNote={Understanding the atomic structure and chemistry of internal interfaces is often critical to developing interface structure-property relationships. Results are presented from several studies in which Z-contrast scanning transmission electron microscopy (STEM) and electron energy loss spectroscopy (EELS) have been employed to solve the atomic structures of oxide interfaces. The Z-contrast imaging technique directly reveals the projected cation sublattices constituting the interface, while EELS provides chemical and local electronic structure information. Because Z-contrast imaging and EELS can be performed simultaneously, direct correlations between structure and chemistry can be made at the atomic scale. The utility of Z-contrast imaging and EELS is demonstrated in three examples: A ZrO{sub 2} 24{degree} [100] symmetric tilt grain boundary, a NiO-cubic ZrO{sub 2} eutectic interface and a Ni-cubic ZrO{sub 2} metal-ceramic interface. The power and versatility of Z-contrast and EELS for solving interface structures in oxide systems is clearly demonstrated in these three material systems.}, number={15-16}, journal={Acta Materialia}, author={Dickey, EC and Fan, X and Pennycock, SJ}, year={1999}, pages={4061–4068} }
 @inproceedings{grimes_qian_allen_stoyanov_dickey_eklund_1999, title={Magnetic and structural properties of iron nitride and iron carbide ferromagnetic nanoparticles made by laser pyrolysis}, booktitle={Digests of the Intermag Conference}, author={Grimes, CA and Qian, D and Allen, JL and Stoyanov, PG and Dickey, EC and Eklund, PC}, year={1999}, month={Dec} }
 @article{sinnott_andrews_qian_rao_mao_dickey_derbyshire_1999, title={Model of carbon nanotube growth through chemical vapor deposition}, volume={315}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000084321900005&KeyUID=WOS:000084321900005}, DOI={10.1016/S0009-2614(99)01216-6}, abstractNote={This Letter outlines a model to account for the catalyzed growth of nanotubes by chemical vapor deposition. It proposes that their formation and growth is an extension of other known processes in which graphitic structures form over metal surfaces at moderate temperatures through the decomposition of organic precursors. Importantly, the model also states that the form of carbon produced depends on the physical dimensions of the catalyzed reactions. Experimental data are presented that correlate nanotube diameters to the size of the catalyst particles. Nanotube stability as a function of nanotube type, length and diameter are also investigated through theoretical calculations.}, number={1-2}, journal={Chemical Physics Letters}, author={Sinnott, SB and Andrews, R and Qian, D and Rao, AM and Mao, Z and Dickey, EC and Derbyshire, F}, year={1999}, pages={25–30} }
 @article{dickey_pint_alexander_wright_1999, title={Oxidation behavior of platinum-aluminum alloys and the effect of Zr doping}, volume={14}, url={https://app.dimensions.ai/details/publication/pub.1051040360}, DOI={10.1557/JMR.1999.0615}, number={12}, journal={Journal of Materials Research}, author={Dickey, EC and Pint, BA and Alexander, KB and Wright, IG}, year={1999}, pages={4531–4540} }
 @article{dickey_frazer_watkins_hubbard_1999, title={Residual stresses in high-temperature ceramic eutectics}, volume={19}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000083005800033&KeyUID=WOS:000083005800033}, DOI={10.1016/S0955-2219(99)00100-4}, abstractNote={This paper explores residual thermal stresses in directionally solidified ceramic eutectics, a class of materials that has much promise for high-temperature structural applications. Residual strain tensors of both phases in a eutectic composite are measured by single crystal X-ray diffraction techniques. In the analysis the material is treated as fully anisotropic and the strain tensors, subsequently converted to stress tensors, are measured. Results are presented for two oxide eutectics, NiO–cubic ZrO2 and YAG–Al2O3, the former having a large thermal expansion mismatch between the two phases and the latter having similar thermal expansion properties. It is discovered that large residual stresses (of the order of 1 GPa) can be present at room temperature in as-processed eutectic materials unless the thermal expansion behaviors of the constituent materials are very similar. Ultimately these measurements not only elucidate the stress state but, when compared to theory, give information about the degree of interfacial constraint between the two phases.}, number={13-14}, journal={Journal of the European Ceramic Society}, author={Dickey, EC and Frazer, CS and Watkins, TR and Hubbard, CR}, year={1999}, pages={2503–2509} }
 @article{koduri_sunkara_dickey_frazier_babu_1999, title={Structural and electrochemical characterisation of metal doped diamondlike carbon films}, volume={15}, url={https://app.dimensions.ai/details/publication/pub.1002759178}, DOI={10.1179/026708499101516713}, abstractNote={The structural and electrochemical characteristics of metal doped diamondlike carbon films with conductivities higher that 5 Ω-1 cm-1 are investigated using TEM and electrochemical characterisation techniques. Cyclic voltammetry of hafnium doped diamondlike carbon films in acidic solutions shows that these films are electrochemically stable compared with pure hafnium metal surfaces. Highly doped Cr–DLC films show the presence of metal dopant in the form of nanoclusters while moderately doped films show randomly dispersed chromium metal dopant. In addition, these Cr–DLC films with nanoclusters of metal dopant show two orders of magnitude enhancement in electrochemical activity with gas evolution in acidic environments compared with the Cr–DLC films with randomly dispersed metal dopant. This difference is attributed to possible electrocatalytic activity of nanoclusters.}, number={5}, journal={Surface Engineering}, author={Koduri, P and Sunkara, MK and Dickey, EC and Frazier, C and Babu, SV}, year={1999}, pages={373–376} }
 @article{fan_dickey_pennycook_sunkara_1999, title={Z-contrast imaging and electron energy-loss spectroscopy analysis of chromium-doped diamond-like carbon films}, volume={75}, url={https://app.dimensions.ai/details/publication/pub.1057689256}, DOI={10.1063/1.125134}, abstractNote={Views Icon Views Article contents Figures & tables Video Audio Supplementary Data Peer Review Share Icon Share Twitter Facebook Reddit LinkedIn Tools Icon Tools Reprints and Permissions Cite Icon Cite Search Site Citation X. Fan, E. C. Dickey, S. J. Pennycook, M. K. Sunkara; Z-contrast imaging and electron energy-loss spectroscopy analysis of chromium-doped diamond-like carbon films. Appl. Phys. Lett. 1 November 1999; 75 (18): 2740–2742. https://doi.org/10.1063/1.125134 Download citation file: Ris (Zotero) Reference Manager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentAIP Publishing PortfolioApplied Physics Letters Search Advanced Search |Citation Search}, number={18}, journal={Applied Physics Letters}, author={Fan, X and Dickey, EC and Pennycook, SJ and Sunkara, MK}, year={1999}, pages={2740–2742} }
 @book{grimes_stoyanov_seitz_doherty_dickey_1998, title={A remotely interrogatable magnetochemical sensor for environmental monitoring}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000074665200008&KeyUID=WOS:000074665200008}, journal={1998 Ieee Aerospace Conference Proceedings, Vol 5}, author={Grimes, CA and Stoyanov, P and Seitz, WR and Doherty, SA and Dickey, EC}, year={1998}, pages={87–92} }
 @inproceedings{grimes_stoyanov_seitz_doherty_dickey_1998, title={A remotely interrogatable magnetochemical sensor for environmental monitoring}, booktitle={1998 IEEE AEROSPACE CONFERENCE PROCEEDINGS, VOL 5}, author={Grimes, CA and Stoyanov, P and Seitz, WR and Doherty, SA and Dickey, EC}, year={1998}, pages={87–92} }
 @article{chen_haddon_fang_rao_lee_dickey_grulke_pendergrass_chavan_haley_et al._1998, title={Chemical attachment of organic functional groups to single-walled carbon nanotube material}, volume={13}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000075621600011&KeyUID=WOS:000075621600011}, DOI={10.1557/JMR.1998.0337}, number={9}, journal={Journal of Materials Research}, author={Chen, Y and Haddon, RC and Fang, S and Rao, AM and Lee, WH and Dickey, EC and Grulke, EA and Pendergrass, JC and Chavan, A and Haley, BE and et al.}, year={1998}, pages={2423–2431} }
 @article{grigorian_williams_fang_sumanasekera_loper_dickey_pennycook_eklund_1998, title={Reversible intercalation of charged iodine chains into carbon nanotube ropes}, volume={80}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000074313000025&KeyUID=WOS:000074313000025}, DOI={10.1103/PhysRevLett.80.5560}, abstractNote={We report intercalation of charged polyiodide chains into the interstitial channels in a single-wall carbon nanotube (SWNT) rope lattice, suggesting a new carbon chemistry for nanotubes, distinctly different from that of graphite and ${\mathrm{C}}_{60}$. This structural model is supported by results from Raman spectroscopy, x-ray diffraction, $Z$-contrast electron microscopy, and electrical transport data. Iodine-doped SWNTs are found to be air stable, permitting the use of a variety of techniques to explore the effect of charge transfer on the physical properties of these novel quantum wires.}, number={25}, journal={Physical Review Letters}, author={Grigorian, L and Williams, KA and Fang, S and Sumanasekera, GU and Loper, AL and Dickey, EC and Pennycook, SJ and Eklund, PC}, year={1998}, pages={5560–5563} }
 @article{dickey_dravid_nellist_wallis_pennycook_1998, title={Three-dimensional atomic structure of NiO-ZrO2(cubic) interfaces}, volume={46}, url={https://app.dimensions.ai/details/publication/pub.1028274840}, DOI={10.1016/S1359-6454(97)00373-X}, abstractNote={The three-dimensional atomic structure of low-energy NiO–ZrO2(cubic) interfaces is determined through a combination of electron imaging and spectroscopy techniques. High resolution electron microscopy, and Z-contrast STEM imaging with simultaneous electron energy loss spectroscopy are employed as complementary techniques for elucidating the structural and chemical aspects of the interface and associated interfacial relaxation mechaubic) interface. The planar interfaces show an atomically abrupt transition between the two phases which share a common oxygen plane at the boundary. Structural relaxations accommodating the lattice mismatch indicate that the boundary has relaxed to a low-energy configuration. The resulting interface structure is found to facilitate strong bonding across the boundary as is reflected in the fracture behavior of the composite system.}, number={5}, journal={Acta Materialia}, author={Dickey, EC and Dravid, VP and Nellist, PD and Wallis, DJ and Pennycook, SJ}, year={1998}, pages={1801–1816} }
 @book{dravid_dickey_revcolevschi_1998, title={Towards (predictive) structure-property relationships for heterophase interfaces in oxides}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:000072465300020&KeyUID=WOS:000072465300020}, journal={Boundaries & Interfaces in Materials: the David A. Smith Symposium}, author={Dravid, VP and Dickey, EC and Revcolevschi, A}, year={1998}, pages={169–177} }
 @inproceedings{dravid_dickey_revcolevschi_1998, title={Towards (predictive) structure-property relationships for heterophase interfaces in oxides}, booktitle={BOUNDARIES & INTERFACES IN MATERIALS: THE DAVID A. SMITH SYMPOSIUM}, author={Dravid, VP and Dickey, EC and Revcolevschi, A}, year={1998}, pages={169–177} }
 @inbook{dickey_dravid_pennycook_nellist_wallis_1997, title={Combined-techniques approach to elucidating crystalline interface atomic structure}, volume={466}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:A1997BJ67H00007&KeyUID=WOS:A1997BJ67H00007}, booktitle={Atomic Resolution Microscopy of Surfaces and Interfaces}, author={Dickey, EC and Dravid, VP and Pennycook, SJ and Nellist, PD and Wallis, DJ}, year={1997}, pages={45–50} }
 @inproceedings{dickey_dravid_pennycook_nellist_wallis_1997, title={Combined-techniques approach to elucidating crystalline interface atomic structure}, volume={466}, booktitle={MRS Online Proceedings Library}, author={Dickey, EC and Dravid, VP and Pennycook, SJ and Nellist, PD and Wallis, DJ}, year={1997}, pages={45–50} }
 @inbook{pennycook_nellist_chisholm_browning_wallis_dickey_1997, title={Determination of atomic structure at surfaces and interfaces by high-resolution stem}, volume={466}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:A1997BJ67H00001&KeyUID=WOS:A1997BJ67H00001}, booktitle={Atomic Resolution Microscopy of Surfaces and Interfaces}, author={Pennycook, SJ and Nellist, PD and Chisholm, MF and Browning, ND and Wallis, DJ and Dickey, EC}, year={1997}, pages={3–11} }
 @inproceedings{pennycook_nellist_chisholm_browning_wallis_dickey_1997, title={Determination of atomic structure at surfaces and interfaces by high-resolution stem}, volume={466}, booktitle={MRS Online Proceedings Library}, author={Pennycook, SJ and Nellist, PD and Chisholm, MF and Browning, ND and Wallis, DJ and Dickey, EC}, year={1997}, pages={3–11} }
 @article{dickey_dravid_hubbard_1997, title={Interlamellar residual stresses in single grains of NiO-ZrO2(cubic) directionally solidified eutectics}, volume={80}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:A1997YG20300002&KeyUID=WOS:A1997YG20300002}, DOI={10.1111/j.1151-2916.1997.tb03193.x}, abstractNote={Phase-to-phase residual stresses due to thermal expansion mismatch were measured in lamellar NiO-ZrO2(cubic) directionally solidified eutectics (DSEs). The triaxial strain tensors for both phases were measured using single-crystal X-ray diffractometry techniques on isolated grains of the DSE. From the strain tensors, the stress tensors were calculated, taking into account the full elastic anisotropy of the phases. The resulting stress tensors indicated that very large compressive stresses accumulated in ZrO2 whereas large tensile stresses were amassed in NiO parallel to the lamellae during the solidification process. The large magnitudes of the stresses indicated that the interfaces between the lamellae were very well bonded and did not facilitate slip or other stress-relieving processes.}, number={11}, journal={Journal of the American Ceramic Society}, author={Dickey, EC and Dravid, VP and Hubbard, CR}, year={1997}, pages={2773–2780} }
 @article{dickey_dravid_nellist_wallis_pennycook_revcolevschi_1997, title={Structure and bonding at Ni-ZrO2 (cubic) interfaces formed by the reduction of a NiO-ZrO2 (cubic) composite}, volume={3}, url={http://gateway.webofknowledge.com/gateway/Gateway.cgi?GWVersion=2&SrcAuth=ORCID&SrcApp=OrcidOrg&DestLinkType=FullRecord&DestApp=WOS_CPL&KeyUT=WOS:A1997YC77200006&KeyUID=WOS:A1997YC77200006}, DOI={10.1017/S1431927697970343}, abstractNote={Structure and Bonding at NiFATAL ERROR -- Missing abstract.ndash;ZrO 2 (Cubic) Interfaces Formed by the Reduction of a NiOFATAL ERROR -- Missing abstract.ndash;ZrO 2 (Cubic) Composite}, number={5}, journal={Microscopy and Microanalysis}, author={Dickey, EC and Dravid, VP and Nellist, PD and Wallis, DJ and Pennycook, SJ and Revcolevschi, A}, year={1997}, pages={443–450} }
 @inproceedings{dickey_1992, title={Automotive plastics recycling: Anticipating legislative demands}, url={https://app.dimensions.ai/details/publication/pub.1099402702}, DOI={10.4271/920835}, booktitle={SAE Technical Papers}, author={Dickey, EC}, year={1992}, month={Jan} }