@article{conrad_yang_2013, title={Effect of the strength of an AC electric field compared to DC on the sintering rate and related grain size of zirconia (3Y-TZP)}, volume={559}, ISSN={["1873-4936"]}, DOI={10.1016/j.msea.2012.08.146}, abstractNote={The influence of the strength of an initial 60 Hz AC field Eo=1–50 V/cm on the sintering rate and corresponding grain size of yttria-stabilized zirconia (3Y-TZP) was determined and compared with an equivalent DC field. For both field types the sintering rate increased and the grain size decreased with field strength up to a critical value, beyond which no further effect occurred. The AC field however had a greater effect than the DC field over the entire field strength range. The major factor responsible for the enhanced sintering rate with both field types was concluded to be retardation of grain growth by the field. The retardation was in turn attributed to a reduction in the grain boundary energy by the interaction of the field with the space charge. Analysis of the results employing the absolute reaction rate theory gave magnitudes of the space charge potential and corresponding grain boundary energy in accord with reported values, but were larger with AC field than with DC. Factors which could contribute to the greater effect of an AC field compared to DC are suggested.}, journal={MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING}, author={Conrad, Hans and Yang, Di}, year={2013}, month={Jan}, pages={591–594} }
 @article{conrad_yang_2011, title={Dependence of the sintering rate and related grain size of yttria-stabilized polycrystalline zirconia (3Y-TZP) on the strength of an applied DC electric field}, volume={528}, ISSN={["1873-4936"]}, DOI={10.1016/j.msea.2011.08.022}, abstractNote={The sintering rate of 3Y-TZP increased with increase in initial applied DC electric field strength up to 20 V/cm; no further effect however occurred at 50 V/cm. Analysis of the data confirmed the earlier finding that the increase in sintering rate by the field resulted mainly from a retardation of grain growth. It was further determined that the retardation resulted from a reduction in the grain boundary energy, which provides the driving force. The initial field of 20 V/cm reduced the grain boundary energy to essentially nil, thereby accounting for the fact that no further decrease in grain size occurred at the higher field strength. The reduction in the grain boundary energy by the field is attributed to the interaction of the field with the space charge.}, number={29-30}, journal={MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING}, author={Conrad, Hans and Yang, Di}, year={2011}, month={Nov}, pages={8523–8529} }
 @article{yang_conrad_2011, title={Enhanced sintering rate and finer grain size in yttria-stablized zirconia (3Y-TZP) with combined DC electric field and increased heating rate}, volume={528}, ISSN={["1873-4936"]}, DOI={10.1016/j.msea.2010.10.041}, abstractNote={The influence of heating rate dT/dt = 2–25 °C/min on sintering of yttria-stabilized ZrO2 (3Y-TZP) powder without and with a small initial DC electric field (E0 = 13.9 V/cm) was determined. An increase in dT/dt and the application of electric field reduced both the sintering time and the grain size at a given density. Employing the master sintering curve approach it was determined that the apparent activation energy Q for sintering was 500 ± 5 kJ/mole, essentially independent of dT/dt and E. A major factor in the effects of dT/dt and E on the sintering rate is their reduction of the grain size. It is proposed that retardation of grain growth by the field results from the interaction of the field with the space charge at the grain boundaries.}, number={3}, journal={MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING}, author={Yang, Di and Conrad, Hans}, year={2011}, month={Jan}, pages={1221–1225} }
 @article{yang_raj_conrad_2010, title={Enhanced Sintering Rate of Zirconia (3Y-TZP) Through the Effect of a Weak dc Electric Field on Grain Growth}, volume={93}, ISSN={["0002-7820"]}, DOI={10.1111/j.1551-2916.2010.03905.x}, abstractNote={ We show, for the first time, that a dc electric field of 20 V/cm shifts the densification curve to a lower temperature in constant heating rate experiments with yttria‐stabilized tetragonal zirconia powder (3Y‐TZP). The enhanced sintering rate is ascribed, at least in part, to the reduced rate of grain growth under the applied field, consistent with earlier experiments on the influence of such fields on grain size in superplastic deformation and isothermal grain growth in zirconia polycrystals. }, number={10}, journal={JOURNAL OF THE AMERICAN CERAMIC SOCIETY}, author={Yang, Di and Raj, Rishi and Conrad, Hans}, year={2010}, month={Oct}, pages={2935–2937} }
 @article{yang_conrad_2010, title={Enhanced sintering rate of zirconia (3Y-TZP) by application of a small AC electric field}, volume={63}, ISSN={["1359-6462"]}, DOI={10.1016/j.scriptamat.2010.04.030}, abstractNote={A small initial electric field E0 = 13.9 V cm−1 enhanced the sintering rate of zirconia (3Y-TZP) powder, with a 60 Hz AC field having a greater effect than a DC field. The enhancement with both fields was in accord with the retardation of grain growth observed directly by scanning electron microscopy and with that which occurred during grain growth and plastic deformation. Some factors which could contribute to the observed behavior are given.}, number={3}, journal={SCRIPTA MATERIALIA}, author={Yang, Di and Conrad, Hans}, year={2010}, month={Aug}, pages={328–331} }
 @article{conrad_yang_2010, title={Influence of an applied dc electric field on the plastic deformation kinetics of oxide ceramics}, volume={90}, ISSN={["1478-6443"]}, DOI={10.1080/14786430903304137}, abstractNote={A modest dc electric field markedly reduced the tensile flow stress at high temperatures in three polycrystalline oxides, i.e. MgO, Al2O3 and yttria-stabilized tetragonal ZrO2 (Y-TZP). The reduction in flow stress ΔσE in Y-TZP consisted of three components: (i) ΔσT due to Joule heating, (ii) a rapid, reversible component obtained in on-off and electric field step tests and (iii) the cumulative effect of the field on microstructure. Only ΔσT and occurred in MgO and Al2O3. It is concluded that results from a reduction in the electrochemical potential for the formation of vacancies corresponding to the diffusion of the rate-controlling ion in the space-charge at the grain boundary. The calculated magnitude of the space-charge zone width and its temperature and solute composition dependence are in accord with theory and experiment; is attributed mainly to the retardation of grain growth by the field. The retardation could be due to one or more of the following effects of the field on the space-charge zone: (i) an increase in the segregated solute ions, (ii) a decrease in grain boundary energy and (iii) a decrease in solute ion mobility.}, number={9}, journal={PHILOSOPHICAL MAGAZINE}, author={Conrad, Hans and Yang, Di}, year={2010}, pages={1141–1157} }
 @article{conrad_yang_2010, title={On the rate-controlling mechanism during the plastic deformation of nanocrystalline Cu}, volume={45}, ISSN={["1573-4803"]}, DOI={10.1007/s10853-010-4703-1}, number={22}, journal={JOURNAL OF MATERIALS SCIENCE}, author={Conrad, Hans and Yang, Di}, year={2010}, month={Nov}, pages={6166–6169} }
 @article{yang_conrad_2009, title={Effect of electropulsing on the tensile flow stress of ultrafine-grained 3Y-TZP at 1400 degrees C}, volume={100}, ISSN={["2195-8556"]}, DOI={10.3139/146.101784}, abstractNote={Abstract}, number={1}, journal={INTERNATIONAL JOURNAL OF MATERIALS RESEARCH}, author={Yang, Di and Conrad, Hans}, year={2009}, month={Jan}, pages={76–80} }
 @article{conrad_yang_2008, title={Effect of an alternating current electric field on the plastic deformation of ultrafine-grained 3Y-TZP at 1400 degrees C and 1500 degrees C}, volume={39A}, ISSN={["1073-5623"]}, DOI={10.1007/s11661-007-9396-y}, number={2}, journal={METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE}, author={Conrad, Hans and Yang, Di}, year={2008}, month={Feb}, pages={272–278} }
 @article{conrad_yang_becher_2008, title={Effect of an applied electric field on the flow stress of ultrafine-grained 2.5Y-TZP at high temperatures}, volume={477}, ISSN={["1873-4936"]}, DOI={10.1016/j.msea.2007.05.057}, abstractNote={Application of a dc electric field (E = 46 V/cm) during the tensile deformation of an ultrafine-grained 2.5Y-TZP (d = 350 nm) at 1450 °C resulted in a significant reduction in the flow stress σ, which reversed upon removal of the field. At strains ϵ ≤ 0.6, the reduction in flow stress ΔσE consisted of two components: (a) a rapid initial decrease in stress (ΔσE*) due to the effect of the field on the deformation mechanism(s) and (b) a longer-time decrease in stress (ΔσT) due to Joule heating, giving ΔσE=ΔσE*+ΔσT. At ϵ > 0.6, an additional contribution (ΔσEstr) occurred, which was attributed to a change in defect structure, e.g., grain growth and cavitation. It was concluded that the rate-controlling mechanism in the present tests is grain boundary sliding accommodated by lattice diffusion of the Zr ions with a threshold stress σo, giving an acting effective stress σe = σ − σo. It was determined for this case that ΔσE* contained reductions in both the effective stress (Δσe,E*) and in the threshold stress (Δσo,E). Analysis of the behavior in terms of an electrochemical potential for vacancy formation showed that Δσe,E* and Δσo,E are related to changes in the electric field potential pertaining to the space charge at the grain boundaries. The calculated width of the space charge region acted on by the electric field was 3–5 nm in the temperature range of 1450–1550 °C.}, number={1-2}, journal={MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING}, author={Conrad, H. and Yang, Di and Becher, P.}, year={2008}, month={Mar}, pages={358–365} }
 @article{conrad_yang_becher_2008, title={Plastic deformation of ultrafine-grained 2.5Y-TZP exposed to a dc electric field with an air gap}, volume={496}, ISSN={["0921-5093"]}, DOI={10.1016/j.msea.2008.07.012}, abstractNote={Abstract The influence on the tensile flow stress of ultrafine-grained 2.5Y-TZP at 1450 °C by a dc electric field with an air gap between the negative electrodes and the positive specimen was determined in two test procedures: Type a, in which the field is applied continuously from the very beginning up to a fixed strain ɛ  ≈ 0.2 and Type b, in which the field is alternately applied and removed following the prestrain ɛ  ≈ 0.2 without and with the field. A larger reduction in the flow stress by the field occurred in the Type a test compared to the Type b. Moreover, a larger reduction occurred in the Type b test when the prestrain was with a field applied compared to without. Both of these behaviors are attributed to a retardation of dynamic grain growth by the field. The reduction in the flow stress by the field in the Type b test was in accord with a decrease in the electrochemical potential for the formation of vacancies corresponding to the lattice diffusion of the rate-controlling Zr ions. The results in the present tests were in general accord with those obtained previously in which both the positive and negative electrodes made direct contact with the specimen. This indicates that neither the orientation of the field nor the presence of an air gap has significant influence on the electric field dependence of the flow stress.}, number={1-2}, journal={MATERIALS SCIENCE AND ENGINEERING A-STRUCTURAL MATERIALS PROPERTIES MICROSTRUCTURE AND PROCESSING}, author={Conrad, H. and Yang, Di and Becher, P.}, year={2008}, month={Nov}, pages={9–13} }
 @article{conrad_yang_2007, title={Effect of DC electric field on the tensile deformation of ultrafine-grained 3Y-TZP at 1450-1600 degrees C}, volume={55}, ISSN={["1873-2453"]}, DOI={10.1016/j.actamat.2007.08.032}, abstractNote={Two test types were employed to determine the effect of DC electric field E = 5–8.3 V cm−1 applied in the loading direction on the tensile flow stress of 3Y-TZP (do = 0.44 μm) at 1450–1600 °C. In type a, the field was applied continuously throughout the tensile test; in type b, the field was alternately applied and removed during the course of the tensile test. The field reduced the flow stress in both test types, but with an appreciably larger effect in the type a tests. The field, however, had no discernable effect on the stress exponent n=∂logε˙/∂logσ determined by strain rate change tests. The reduction in flow stress in the type b tests reversed upon removal of the field. It was interpreted to result from both Joule heating and a decrease in the energy to form the rate-controlling Zr4+ vacancies in the space charge zone adjacent to the grain boundaries. The calculated width of the space charge zone λ (=1.5–7.8 nm) and the ratio of the applied electric potential to the reduction in stress Δϕa/Δσ (=18–19 μV/MPa) were in accord with predictions. The larger reduction in the flow stress in the type a tests is attributed to a greater retardation of grain growth by the field.}, number={20}, journal={ACTA MATERIALIA}, author={Conrad, H. and Yang, D.}, year={2007}, month={Dec}, pages={6789–6797} }
 @article{conrad_yang_2002, title={Effect of an electric field on the plastic deformation kinetics of electrodeposited Cu at low and intermediate temperatures}, volume={50}, ISSN={["1873-2453"]}, DOI={10.1016/S1359-6454(02)00109-X}, abstractNote={The plastic deformation kinetics of electrodeposited (EP) Cu foil with grain size d=0.6μm was determined at 293–448 K without and with a concurrent electrostatic field E=2.5kV/cm and compared with that for vapor-deposited (VP) Cu foil tested at 77–473 K without a field. The electric field produced a 20–25% decrease in the flow stress of the EP Cu. The apparent activation volume v=kT∂lnε̇/∂σ both without and with electric field, exhibited a minimum at 350–375 K. The strain rate-controlling mechanism at T≤350K was concluded to be grain boundary shear promoted by the pile-up of dislocations at grain boundaries, while that at T=373–473K was concluded to be the intersection of dislocations. The major effect of the electric field was to give a reduction in the dislocation density produced by straining, which was related to the electric charge density at the specimen surface.}, number={11}, journal={ACTA MATERIALIA}, author={Conrad, H and Yang, D}, year={2002}, month={Jun}, pages={2851–2866} }
 @article{conrad_yang_2002, title={Plastic deformation kinetics of electrodeposited Cu foil at low and intermediate homologous temperatures}, volume={31}, ISSN={["0361-5235"]}, DOI={10.1007/s11664-002-0148-x}, number={4}, journal={JOURNAL OF ELECTRONIC MATERIALS}, author={Conrad, H and Yang, D}, year={2002}, month={Apr}, pages={304–312} }
 @article{yang_conrad_2002, title={Plastic deformation kinetics of fine-grained MgO in tension}, volume={37}, ISSN={["0022-2461"]}, DOI={10.1023/A:1013734011298}, number={3}, journal={JOURNAL OF MATERIALS SCIENCE}, author={Yang, D and Conrad, H}, year={2002}, month={Feb}, pages={615–620} }
 @article{karoui_karoui_kvit_rozgonyi_yang_2002, title={Role of nitrogen related complexes in the formation of defects in silicon}, volume={80}, ISSN={["1077-3118"]}, DOI={10.1063/1.1462874}, abstractNote={Defect size and density distributions were obtained as a function of depth in nitrogen doped CZ silicon (N-CZ) following Hi–Lo–Hi and Lo–Hi annealing, using an oxygen precipitate profiler. The defects were also delineated by Wright etching and Nomarski optical microscopy on both cleaved and bevel polished samples. In addition to the enhanced precipitation and absence of voids previously reported for N-CZ Si, an unexpected mode of precipitation has been found near the annealed wafer surface, just above the traditional denuded zone. This oxynitride precipitate is discussed with regard to N-related complex interactions and point defect supersaturations/injection. High resolution transmission electron microscopy revealed that most precipitates have an octahedral shape with two distinct amorphous phases, which reflect a transition from an initial phase containing both N and O to one with primarily O, as verified with Z-contrast TEM and electron energy loss spectroscopy.}, number={12}, journal={APPLIED PHYSICS LETTERS}, author={Karoui, A and Karoui, FS and Kvit, A and Rozgonyi, GA and Yang, D}, year={2002}, month={Mar}, pages={2114–2116} }
 @article{karoui_karoui_yang_rozgonyi_2002, title={Role of nitrogen-related complexes in the formation of defects in N-Cz silicon wafers}, volume={82-84}, number={2002}, journal={Gettering and defect engineering in semiconductor technology}, author={Karoui, A. and Karoui, F. S. and Yang, D. and Rozgonyi, G. A.}, year={2002}, pages={69–74} }
 @article{yang_conrad_2001, title={Exploratory study into the effects of an electric field and of high current density electropulsing on the plastic deformation of TiAl}, volume={9}, ISSN={["0966-9795"]}, DOI={10.1016/S0966-9795(01)00094-2}, abstractNote={The effects of an external electric field (2 kV/cm) and of high density electric current pulsing (2×104 A/cm2, 60 μs duration and 20 pulses per second) on the stress–strain curve of TiAl in compression at 600 °C were determined. The field gave a significant reduction in yield stress followed by a moderate increase in strain hardening. In contrast, electropulsing increased the yield stress and gave a smaller increase in strain hardening. The effects of the electric field and of electropulsing developed during the early stages of plastic deformation (ε<∼2%) and were retained upon subsequent straining without the field or current. Moreover, initial straining (ε<∼2%) without an electric field gave a microstructure which did not respond to the electric field applied during subsequent straining. The results suggest that the electric field and the electropulsing had an influence on the microstructure which developed at small strain through an effect on one or more of the following: (a) stacking fault energy, (b) twinning energy or (c) antiphase boundary energy.}, number={10-11}, journal={INTERMETALLICS}, author={Yang, D and Conrad, H}, year={2001}, pages={943–947} }
 @article{conrad_yang_2000, title={Influence of an electric field on the plastic deformation of fine-grained MgO at high homologous temperatures}, volume={48}, ISSN={["1359-6454"]}, DOI={10.1016/S1359-6454(00)00203-2}, abstractNote={The effect of a dc electric field up to 385 V/cm on the stress–strain behavior in tension of fine-grained MgO (do=5.3 μm) was determined at 1500–1600°C. The field produced a decrease in the flow stress and an increase in the elongation. The reduction in flow stress was reversible and proportional to the field strength, amounting to ∼50% of the flow stress for E=220 V/cm. The field had only little, if any, influence on the stress exponent n=∂lnε̇/∂lnσ, which had a value of ∼1.0, indicating that it did not change the rate-controlling mechanism. The decrease in flow stress produced by the field is given byΔσ∗E=ZeExsc/Ωwhere Z=+2 is the charge on the rate-controlling Mg2+ ions, e is the electron charge, E is the field strength, xsc is the width of the space charge region and Ω is the atomic volume. The present results are the first of their kind which provide experimental support for the use of an electrochemical potential in diffusion flux equations pertaining to the plastic deformation of ceramic materials.}, number={16}, journal={ACTA MATERIALIA}, author={Conrad, H and Yang, D}, year={2000}, month={Oct}, pages={4045–4052} }
 @article{yang_conrad_1999, title={Plastic deformation of fine-grained Al2O3 in the presence of an electric field}, volume={41}, ISSN={["1359-6462"]}, DOI={10.1016/S1359-6462(99)00126-8}, abstractNote={The effect of electric field/current on creep deformation was examined in fine-grained 8 mol% Y2O3 stabilized cubic ZrO2 (8Y-CSZ) under direct and alternative current (DC and AC) conditions. Even at similar sample temperature of 1160–1170 °C, although the electric fields/currents accelerate the deformation of 8Y-CSZ, the acceleration effect (athermal effect), which cannot be explained by an increase of the sample temperature due to Joule heating, is much pronounced in AC than in DC. Under the deformation without the electric field/current, the creep behavior can be characterized by diffusional creep processes with a stress exponent of n ≈ 1, whereas under DC and AC, the predominant mechanism changes to grain boundary sliding (GBS) with n ≈ 2. This indicates that the athermal effect under the electric field/current changes the deformation mechanism from diffusional creep to GBS mechanisms by enhancing GBS and its rate controlling process of cation diffusivity, especially in AC.}, number={4}, journal={SCRIPTA MATERIALIA}, author={Yang, D and Conrad, H}, year={1999}, month={Jul}, pages={397–401} }
 @article{conrad_yang_1999, title={The rate-controlling mechanism(s) during plastic deformation of polycrystalline NaCl at 0.28-0.75 T-M}, volume={34}, DOI={10.1023/A:1004537300154}, number={4}, journal={Journal of Materials Science}, author={Conrad, H. and Yang, D.}, year={1999}, pages={821–826} }
 @article{lee_woolcott_basceri_lee_streiffer_kingon_yang_1998, title={Electrical properties of (Ba, Sr)TiO3 thin films prepared by liquid delivery MOCVD}, volume={32 pt.4}, number={suppl.}, journal={Journal of the Korean Physical Society}, author={Lee, W. J. and Woolcott, R. R. and Basceri, C. and Lee, H. Y. and Streiffer, S. K. and Kingon, A. I. and Yang, D. Y.}, year={1998}, pages={1652–1656} }
 @article{yang_conrad_1998, title={Grain size dependence of electroplastic effect in NaCl}, volume={97}, number={6}, journal={British Ceramic Transactions}, author={Yang, D. and Conrad, H.}, year={1998}, pages={263–267} }
 @article{yang_conrad_1998, title={Influence of an electric field on grain growth in extruded NaCl}, volume={38}, ISSN={["1359-6462"]}, DOI={10.1016/S1359-6462(98)00042-6}, abstractNote={Spark plasma sintering (SPS), also known as pulsed electric current sintering (PECS) or field-assisted sintering technique (FAST), belongs to a class of powder metallurgy techniques. In SPS, the sample is simultaneously subjected to a uniaxial pressure and electrical current in a vacuum or protective atmosphere. Although the fundamental principles of this procedure were first proposed over 50 years ago, SPS acquired major importance only within the last 20 years. Scholars come to realize that SPS technique enables control of the powder surface condition, atomic diffusion behavior, and phase stability and crystal growth behavior, as well as accelerating densification of hard-to-sinter materials. This review summarizes the latest research findings with respect to experimental procedures, densification behaviors, microstructural characteristics, and mechanical properties of various traditional and novel materials synthesized using SPS, mainly highlighting the heating mechanisms in SPS and the effects induced by multi-physical fields on materials. In addition, influences of operating parameters containing current, voltage, and uniaxial pressure on product characteristics are reviewed for a wide range of materialsincluding hard-to-sinter materials, carbon-containing materials, nanocrystalline materials, non-equilibrium materials, gradient materials, interconnect materials, complex shape materials, and advanced functional materials.}, number={9}, journal={SCRIPTA MATERIALIA}, author={Yang, D and Conrad, H}, year={1998}, month={Apr}, pages={1443–1448} }
 @article{yang_conrad_1998, title={Influence of an electric field on the plastic deformation of polycrystalline NaCl at elevated temperatures}, volume={46}, ISSN={["1359-6454"]}, DOI={10.1016/S1359-6454(97)00431-X}, abstractNote={Abstract The effect of a d.c. electric field of 1 kV/cm on the plastic deformation of polycrystalline 99.9% NaCl was determined in compression at 23–532°C (0.28–0.75  T M ) and strain rate e =8.3×10 −4  s −1 . Upon removing the effect of Joule heating it was found that the reduction in the flow stress produced by the field increased with temperature from 0.28 to 0.4  T M , reached a maximum at 0.4  T M and then decreased, becoming nil at 0.75  T M . It is proposed that the reduction in flow stress resulted from an enhancement of cross-slip due to an increase in stacking fault energy. The field had no detectable effect on the plastic deformation kinetics at constant structure in the temperature range 0.28–0.6  T M (cutting of forest dislocations), nor did it appear to have a significant influence on dislocation glide and climb at 0.75  T M .}, number={6}, journal={ACTA MATERIALIA}, author={Yang, D and Conrad, H}, year={1998}, month={Mar}, pages={1963–1968} }
 @article{lee_basceri_streiffer_kingon_yang_park_kim_1998, title={Ir and Ru bottom electrodes for (Ba, Sr) TiO3 thin films deposited by liquid delivery source chemical vapor deposition}, volume={323}, ISSN={["0040-6090"]}, DOI={10.1016/S0040-6090(97)01043-2}, abstractNote={The electrical properties and surface morphologies of (Ba, Sr)TiO3 thin films, with various bottom electrode structures, deposited by liquid delivery metal organic chemical vapor deposition were investigated. Ir and Ru films as a bottom electrode with varying deposition temperatures were prepared onto SiO2 and polySi substrate structures using ion beam sputtering technique. It is observed that electrical properties of BST films deposited by liquid delivery MOCVD was changed with the deposition temperatures of Ir and Ru as well as substrate structures. Furthermore, it is revealed that these variations in leakage current could be strongly related with the roughness of BST films.}, number={1-2}, journal={THIN SOLID FILMS}, author={Lee, WJ and Basceri, C and Streiffer, SK and Kingon, AI and Yang, DY and Park, Y and Kim, HG}, year={1998}, month={Jun}, pages={285–290} }
 @article{kim_choi_kim_yang_1998, title={The effects of PbTiO3 thin template layer and Pt/RuO2 hybrid electrode on the ferroelectric properties of sol-gel derived PZT thin film}, volume={325}, ISSN={["0040-6090"]}, DOI={10.1016/S0040-6090(98)00486-6}, abstractNote={Lead zirconate titanate, Pb(Zr0.52Ti0.48)O3 (PZT) thin film with a thin PbTiO3 template layer was successfully fabricated onto Pt/RuO2 hybrid electrode by using a new alkoxide-alkanolamine sol-gel method. The resulting film showed a well-developed dense grain structure with uniform distribution. It was observed that the use of Pt/RuO2 hybrid electrode helped reduce the amount of the Pb2Ru2O7−x second phase as well as the leakage current by about three orders of magnitude. Typical P-E hysteresis loops were observed even at the low applied voltage of 5 V and the measured values of 2Ps, 2Pr and 2Ec were 93 μC/cm2, 48 μC/cm2 and 78 kV/cm, respectively. Polarization versus fatigue characteristics showed little degradation up to 1011 cycles.}, number={1-2}, journal={THIN SOLID FILMS}, author={Kim, SH and Choi, YS and Kim, CE and Yang, DY}, year={1998}, month={Jul}, pages={72–78} }
 @article{yang_conrad_1997, title={Influence of an electric field on the superplastic deformation of 3Y-TZP}, volume={36}, ISSN={["1359-6462"]}, DOI={10.1016/S1359-6462(97)00045-6}, abstractNote={The effect of electric field/current on creep deformation was examined in fine-grained 8 mol% Y2O3 stabilized cubic ZrO2 (8Y-CSZ) under direct and alternative current (DC and AC) conditions. Even at similar sample temperature of 1160–1170 °C, although the electric fields/currents accelerate the deformation of 8Y-CSZ, the acceleration effect (athermal effect), which cannot be explained by an increase of the sample temperature due to Joule heating, is much pronounced in AC than in DC. Under the deformation without the electric field/current, the creep behavior can be characterized by diffusional creep processes with a stress exponent of n ≈ 1, whereas under DC and AC, the predominant mechanism changes to grain boundary sliding (GBS) with n ≈ 2. This indicates that the athermal effect under the electric field/current changes the deformation mechanism from diffusional creep to GBS mechanisms by enhancing GBS and its rate controlling process of cation diffusivity, especially in AC.}, number={12}, journal={SCRIPTA MATERIALIA}, author={Yang, D and Conrad, H}, year={1997}, month={Jun}, pages={1431–1435} }