@article{kim_park_shen_lee_kingon_yoon_kim_2008, title={Thickness dependence of submicron thick Pb(Zr0.3Ti0.7)O-3 films on piezoelectric properties}, volume={34}, ISSN={["0272-8842"]}, DOI={10.1016/j.ceramint.2007.07.016}, abstractNote={The effects of thickness on the piezoelectric and electric properties of tetragonal composition, polycrystalline, (1 1 1)-textured Pb(Zr0.3Ti0.7)O3 films are investigated. The effective piezoelectric coefficient d33 is characterized by a double-beam laser interferometer and is measured to increase with film thickness although extrinsic contribution such as 90° domain wall motion is negligible from the nonlinearity of piezoelectric coefficient. Constituent parameters to affect piezoelectric coefficient such as polarization and dielectric properties were analyzed based on the semiempirical phenomenological equation. The effectiveness of poling was also evaluated as a function of film thickness. These results present that the increase of effective d33 in these tetragonal PZT films can be mainly due to enhanced intrinsic contributions.}, number={8}, journal={CERAMICS INTERNATIONAL}, author={Kim, Dong-Joo and Park, Jung-Hyun and Shen, Dongna and Lee, Joo Won and Kingon, Angus I. and Yoon, Young Soo and Kim, Seung-Hyun}, year={2008}, month={Dec}, pages={1909–1915} }
 @article{kim_maria_kingon_streiffer_2003, title={Evaluation of intrinsic and extrinsic contributions to the piezoelectric properties of Pb(Zr1-xTX)O-3 thin films as a function of composition}, volume={93}, ISSN={["0021-8979"]}, DOI={10.1063/1.1566478}, abstractNote={The piezoelectric, dielectric, and ferroelectric properties of highly (111)-textured, 200-nm-thick polycrystalline lead zirconate titanate (PZT) films have been investigated as a function of Zr/Ti ratio. The distinct peak in piezoelectric coefficient at the morphotropic phase boundary found in bulk PZT ceramics is not observed in thin film PZTs. Measurements of the temperature dependence of relative permittivity and the nonlinear behavior of relative permittivity and piezoelectric coefficient suggest that non-180° domain wall motion in these films is negligible, indicating that the extrinsic contribution to the room temperature permittivity is dominated by only 180° domain wall motion. The semiempirical phenomenological equation relating the piezoelectric coefficient to measured polarization and permittivity values is demonstrated to give an excellent description of the piezoelectric behavior in these films, assuming bulk electrostrictive and elastic coefficients. The small deviation between calculated and measured piezoelectric coefficients as well as the dependence of piezoelectric and polarization behavior on the external field, i.e., hysteresis loop, are suggested to be primarily due to backswitching of 180° domains.}, number={9}, journal={JOURNAL OF APPLIED PHYSICS}, author={Kim, DJ and Maria, JP and Kingon, AI and Streiffer, SK}, year={2003}, month={May}, pages={5568–5575} }
 @article{yoon_wicaksana_kim_kim_kingon_2001, title={Effect of hydrogen on true leakage current characteristics of (Pb,La)(Zr,Ti)O-3 thin-film capacitors with Pt- or Ir-based top electrodes}, volume={16}, ISSN={["2044-5326"]}, DOI={10.1557/JMR.2001.0163}, abstractNote={The degradation behavior of polarization and leakage current characteristics of sol-gel-derived (Pb,La)(Zr,Ti)O3 (PLZT) thin films, with Pt, Ir, and IrO2 top electrodes, by annealing under a 4% H2/96% N2 atmosphere were investigated. The leakage current behaviors of Pt/PLZT/Pt and IrO2/PLZT/Pt capacitors annealed at 300 °C for 20 min in 4% H2 were well consistent with the space-charge-influenced injection model proposed. However, IrO2/PLZT/Pt capacitors recovered at 700 °C for 10 min in Ar ambient after hydrogen anneal were not consistent with the proposed model because a conducting phase of IrPb was formed between the top electrode and PLZT during the recovery anneal at 700 °C in Ar ambient and modified the Schottky barrier height. The true leakage current behavior of IrO2/PLZT/Pt capacitors recovered after hydrogen forming are similar to those of Ir/PLZT/Pt capacitors without the hydrogen-forming gas anneal. The P–E loops of Pt/PLZT/Pt and Ir/PLZT/Pt capacitors showed good recovery through recovery anneal after H2 treatment. However, IrO2/PLZT/Pt capacitors depended on the recovery anneal atmosphere (Ar or O2).}, number={4}, journal={JOURNAL OF MATERIALS RESEARCH}, author={Yoon, SG and Wicaksana, D and Kim, DJ and Kim, SH and Kingon, AI}, year={2001}, month={Apr}, pages={1185–1189} }
 @article{baumann_streiffer_bai_ghosh_auciello_thompson_stemmer_rao_eom_xu_et al._2001, title={Epitaxial Pb(Mg1/3Nb2/3)O-3-PbTiO3 thin films grown by MOCVD}, volume={35}, number={1-4}, journal={Integrated Ferroelectrics}, author={Baumann, P. K. and Streiffer, S. K. and Bai, G. R. and Ghosh, K. and Auciello, O. and Thompson, C. and Stemmer, S. and Rao, R. A. and Eom, C. B. and Xu, F. and et al.}, year={2001}, pages={1881–1888} }
 @article{chen_roeder_kim_maria_kingon_2001, title={Metalorganic chemical vapor deposition Pb(Zr,Ti)O-3 and selected lower electrode structures as a pathway to integrated piezoelectric microelectromechanical systems}, volume={19}, ISSN={["1071-1023"]}, DOI={10.1116/1.1401747}, abstractNote={The actuation mechanism is an important aspect of many micromachined devices. Electrostatic actuation has been the prevailing actuation method due to its relative ease in implementation using conventional silicon microfabrication techniques. Other mechanisms are becoming more accessible to micromachine designs as new materials are introduced into the microfabrication process. Recent progress in nonvolatile memory has led to successful incorporation of Pb(Zr,Ti)O3 (PZT) thin films into microelectronic devices. The present work expands on this area and investigates PZT thin films and electrode/barrier combinations for applications in micromachined devices. Incorporation of PZT thin films into silicon micromachined devices requires electrode systems and deposition techniques that are compatible with silicon microfabrication. In this study, Ir/IrOx and Ir/(Ti,Al)N lower electrode systems were developed to suppress diffusion of reactive species (e.g., Pb) into silicon-based microelectromechanical system devices and to enhance PZT film adhesion. Piezoelectric PZT thin films from 0.3 to 1 μm thick were prepared on silicon wafers with these electrode structures by metalorganic chemical vapor deposition. Hysteresis loops of longitudinal piezoelectric coefficient (d33) were measured by dual-beam interferometry and used to characterize piezoelectric activity in these films. The effective d33 exhibited an apparent dependence on film thickness. d33 values up to 70 pm/V were obtained for 1 μm films, while thinner films exhibited lower d33 values between 54 and 60 pm/V. The dielectric loss (tan δ) was below 2% for most films irrespective of their thickness.}, number={5}, journal={JOURNAL OF VACUUM SCIENCE & TECHNOLOGY B}, author={Chen, IS and Roeder, JF and Kim, DJ and Maria, JP and Kingon, AI}, year={2001}, pages={1833–1840} }
 @article{kim_kim_maria_kingon_streiffer_im_auciello_krauss_2000, title={Influence of Pt heterostructure bottom electrodes on SrBi2Ta2O9 thin film properties}, volume={76}, ISSN={["1077-3118"]}, DOI={10.1063/1.125799}, abstractNote={The properties of SrBi2Ta2O9 (SBT) films, such as remanent polarization and leakage current density, are closely related to the film/electrode interface and surface roughness of the underlying electrode. SBT films grown on stable Pt/TiO2/SiO2/Si and Pt/ZrO2/SiO2/Si substrates exhibit high remanent polarization, low leakage current density, and low voltage saturation as compared to SBT films synthesized on Pt/Ti/SiO2/Si. It is shown that severe diffusion of Ti from the Ti interlayer onto the surface of the Pt bottom electrode and the increased surface roughness of this electrode stack play key roles in degradation of SBT properties.}, number={4}, journal={APPLIED PHYSICS LETTERS}, author={Kim, SH and Kim, DJ and Maria, JP and Kingon, AI and Streiffer, SK and Im, J and Auciello, O and Krauss, AR}, year={2000}, month={Jan}, pages={496–498} }
 @article{hugon_desvignes_agius_vickridge_kim_kingon_2000, title={Narrow resonance profiling study of the oxidation of reactively sputtered Ti1-xAlxN thin films}, volume={161}, ISSN={["0168-583X"]}, DOI={10.1016/S0168-583X(99)00953-2}, abstractNote={The bottom electrode structure used with ferroelectric (FE) and high dielectric constant (HDC) materials requires a material to promote FE or HDC cristallisation (Pt or IrO2) and a material with diffusion barrier properties; this last material being between Pt (or IrO2) film and Si substrate. TiN, TiAlN and TaSiN have been proposed for diffusion applications. Ti1−xAlxN films have drawn much attention as alternatives to TiN diffusion barriers. In this paper we have investigated the effect of Al content on the oxidation resistance of Ti1−xAlxN films prepared by radio frequency reactive sputtering in a mixed Ar+N2 discharge. The concentration depth profiles of both 18O and 27Al were measured before and after the rapid thermal annealing of samples at 750°C for 30 s in 18O2, via the narrow resonances of 18O(p,α)15N at 151 keV (fwhm=100 eV) and 27Al(p,γ)28Si at 992 keV (fwhm=100 eV). It was found that Al incorporation in the films reduces oxide growth. The Al excitation curves indicate a uniform Al content for as deposited Ti1−xAlxN, and reveal Al diffusion to the surface during oxidation, which indicates the formation of an Al rich oxide layer at the Ti1−xAlxN surface. The results suggest that Ti1−xAlxN films with x>0.39 are promising candidates as electrically conductive diffusion barrier layers.}, journal={NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS}, author={Hugon, MC and Desvignes, JM and Agius, B and Vickridge, IC and Kim, DJ and Kingon, AI}, year={2000}, month={Mar}, pages={578–583} }
 @article{letendu_hugon_desvignes_agius_vickridge_kim_kingon_2000, title={Oxidation resistance of TaSiN diffusion barriers}, volume={31}, number={1-4}, journal={Integrated Ferroelectrics}, author={Letendu, F. and Hugon, M. C. and Desvignes, J. M. and Agius, B. and Vickridge, I. and Kim, D. J. and Kingon, A. I.}, year={2000}, pages={315–322} }
 @article{kim_lee_hwang_kim_kingon_2000, title={Thermally induced voltage offsets in Pb(Zr,Ti)O-3 thin films}, volume={77}, ISSN={["1077-3118"]}, DOI={10.1063/1.1324001}, abstractNote={Voltage offset in the polarization-voltage characteristics of Pb(Zr,Ti)O3 (PZT) capacitors was evaluated by a thermal stress process. A thermally induced voltage shift occurs when heating the sample under either remanence or a saturating bias. It was found that the voltage shifts can, to a large extent, be attributed to the role of charged defects and the defect-dipole alignment throughout the films. PZT film with a high Zr/Ti ratio, i.e., rhombohedral compositions exhibited the best imprint resistance. When these films were doped wit up to 6% La, the imprint resistance was further improved. It was also found that B-site donors were more effective in minimizing the voltage shift than A-site donors. However, dopants with the same charge value as Pb, for example, Ca and Sr, did not affect the thermally induced voltage shifts of the films since they could not reduce the charged defects in the films.}, number={19}, journal={APPLIED PHYSICS LETTERS}, author={Kim, SH and Lee, DS and Hwang, CS and Kim, DJ and Kingon, AI}, year={2000}, month={Nov}, pages={3036–3038} }
 @article{kim_kim_lee_park_kingon_nemanich_im_streiffer_1999, title={An optimized process for fabrication of SrBi2Ta2O9 thin films using a novel chemical solution deposition technique}, volume={14}, ISSN={["0884-2914"]}, DOI={10.1557/JMR.1999.0594}, abstractNote={Ferroelectric SrBi2Ta2O9 (SBT) thin films on Pt/ZrO2/SiO2/Si were successfully prepared by using an alkanolamine-modified chemical solution deposition method. It was observed that alkanolamine provided stability to the SBT solution by retarding the hydrolysis and condensation rates. The crystallinity and the microstructure of the SBT thin films improved with increasing annealing temperature and were strongly correlated with the ferroelectric properties of the SBT thin films. The films annealed at 800 °C exhibited low leakage current density, low voltage saturation, high remanent polarization, and good fatigue characteristics at least up to 1010 switching cycles, indicating favorable behavior for memory applications.}, number={11}, journal={JOURNAL OF MATERIALS RESEARCH}, author={Kim, SH and Kim, DJ and Lee, KM and Park, M and Kingon, AI and Nemanich, RJ and Im, J and Streiffer, SK}, year={1999}, month={Nov}, pages={4395–4401} }
 @article{kim_kim_im_kim_kingon_1999, title={Ferroelectric properties of new chemical solution derived SBT thin films for non-volatile memory devices}, volume={16}, ISSN={["1573-4846"]}, DOI={10.1023/A:1008748718231}, number={1-2}, journal={JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY}, author={Kim, SH and Kim, DJ and Im, J and Kim, CE and Kingon, AI}, year={1999}, month={Oct}, pages={57–63} }
 @article{kim_kim_im_streiffer_auciello_maria_kingon_1999, title={Impact of changes in the Pt heterostructure bottom electrodes on the ferroelectric properties of SBT thin films}, volume={26}, DOI={10.1080/10584589908215626}, abstractNote={Abstract The crystallinity and the microstructure of Sr0.8Bi2.3Ta2O9 (SBT) thin films improved with increasing annealing temperature, and strongly influenced the ferroelectric properties. In addition, the properties of SBT films, such as remanent polarization and leakage current density, are closely related to the film/electrode interface and surface roughness of the underlying electrode. SBT films on Pt/TiO2/SiO2/Si and Pt/ZrO2/SiO2/Si substrates exhibited high remanent polarization, low leakage current density, and low voltage saturation as compared to SBT films on Pt/Ti/SiO2/Si substrates. This is deduced to be related to differences in film orientation, electrode roughness, and out-diffusion of Ti onto the surface of the bottom electrode.}, number={1-4}, journal={Integrated Ferroelectrics}, author={Kim, S. H. and Kim, D. J. and Im, J. and Streiffer, S. K. and Auciello, O. and Maria, J. P. and Kingon, A. I.}, year={1999}, pages={955–970} }
 @article{kim_kim_maria_kingon_1999, title={Influences on imprint failure of SrBi2Ta2O9 thin film capacitors}, volume={25}, number={1-4}, journal={Integrated Ferroelectrics}, author={Kim, D. J. and Kim, S. H. and Maria, J. P. and Kingon, A. I.}, year={1999}, pages={691–701} }