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Heterolayered Pb([Zr.sub.1-x][Ti.sub.x])[O.sub.3] thin films with different combinations of constituted layers are examined. The wake-up phenomenon is reduced at elevated temperatures, thus leading to fatigue degradation at a relatively lower number of switching cycles.

The influence of the progressive strain relaxation and the depolarizing-field effect on the thickness dependence of the out-of-plane dielectric response of epitaxial ferroelectric thin films sandwiched between extended metal electrodes is analyzed. The results have shown that the inverse of the measured capacitance has changed with the film thickness almost linearly in most part of the thickness range at the majority of temperatures.

The resonance method was used to study the elastic, dielectric, and piezoelectric properties of several soft and hard piezoelectric lead zirconate titanate (PZT) samples, with compositions near the morphotropic phase boundary (MPB), as a function of temperature ranging between165 to 195 degree Celsius. The results showed that the material coefficients of soft PZT varied significantly more than those of hard PZT under changing temperature conditions.

The short-circuit photocurrent (SC-PHC) in the 200-800 nm wavelength domain was used to investigate the photovoltaic properties of the metal-ferroelectric-metal structures having SrRu[O.sub.3] metal oxide electrodes and Pb(Zr, Ti)[O.sub.3] (PZT) as ferroelectric layer. The band-gap energies evaluated from the PHC spectral distribution for different PZT compositions range between 3.9 to 4.4 eV and it is constantly higher than the reported experimental values on polycrystalline films but agree well with theoretical values.

The effect of Ta substitution on the structural, microstructural, molecular and dielectric characteristics of Pb[Sc(sub)0.5Nb(sub)0.5]O(sub)3 (PSNT), synthesized by mechano-synthesis and conventional mixed oxide methods is studied. It is found that the ceramics show the formation of the materials in a single phase in the rhombohedral structure with the existence of nanodomain.

The microstructural effects on the mechanical and electrical properties of common density PZT95/5-2Nb materials under shock compression were investigated. The results indicate that differences in the porous microstructure of common density materials have little effect on mechanical and electrical shock properties.

Various x-ray diffraction experiments are employed to study the microscopic-scale structures of 0.72Pb([Mg.sub.1/3][Nb.sub.2/3])[O.sub.3]-0.28PbTi[O.sub.3] relaxor ferroelectrics in a high external dc field during phase transition. The results clearly prove that a change in the temperature also leads to a major change in the dominating cluster's orientation, as well as their interaction direction.

Several experiments are conducted to analyze and describe the concentration dependence of the fluorescence quantum efficiency in [Nd.sup.3+] doped lead lanthanum zirconate titanate (PLZT) transparent ferroelectric ceramics. It can be clearly inferred from the results that Nd:PLZT presents lower concentration quenching, as compared to any other laser materials.

Lead-free potassium sodium niobate piezoelectric single crystals substituted with lithium 0.95([K.sub.0.5][Na.sub.0.5])Nb[O.sub.3]-0.05LiNb[O.sub.3] are grown by Bridgman method and their dielectric and piezoelectric properties are analyzed. The observation suggest that 0.95([K.sub.0.5[][a.sub.0.5])Nb[O.sub.3]-0.05LiNb[O.sub.3] single crystal is a good lead-free piezoelectric material.

A study was conducted to investigate magnetoelectric resonance behavior of a simple, bilayered structure of Pb(Zr, Ti)[O.sub.3] ceramic chip and (Tb, Dy)[Fe.sub.2]/epoxy mixture layer. The results have shown three kinds of resonance, which are attributed to the first-order flexural, second-order flexural, and radial resonance modes, respectively.

The influence of stress on phase diagrams and dielectric properties in epitaxial BaTi[O.sub.3] and PbTi[O.sub.3] thin films grown on the dissimilar orthorhombic substrates is analyzed by using a phenomenological Landau-Devonshine theory. The dielectric properties and the tunability of both the films are studied and it is found that the external stress dependence of phase diagrams and dielectric properties depends on the strain anisotropy.

The impact of sintering temperature on the phase transition and dielectrical response in the relaxor ferroelectrics of 0.5PB([Zn.sub.1/3][Nb.sub.2/3])[O.sub.3]-0.5Pb([Zr.sub.0.47][Ti.sub.0.53])[O.sub.3] (0.5PZN-0.5PZT) ceramics near the morphotropic phase boundary (MPB), fabricated by conventional ceramic method are studied. It is observed that the phase of material varied from rhombohedral structure initially to a MPB and then a tetragonal structure as the sintering temperature rose from 900 to 1250 degree Celsius.

Wedge-cut samples of fatigued ferroelectric lead zirconate titanate (PZT) ceramics are investigated using piezoresponse force microscopy along with conventional electrical hysteresis measurements. A broad distribution of coercive fields is observed for PZT/Pt.

The current-voltage (I-V) characteristics are studied in fully integrated commercial Pb[Zr.sub.0.4][Ti.sub.0.6][O.sub.3] thin film (PZT) capacitors with Pt bottom and Ir/IrO2 top electrodes. It is found that standard automated I-V tests are not always appropriate for ferroelectrics due to the large difference in relaxation times for current transients at different fields.

A study on the influence of domain switching on the evolution of macroscopic polarization in the ferroelectric [Pb(Mg1/3Nb2/3).sub.1-x][Ti.sub.x]O3 material is conducted. Results reveal that stress depolarization is controlled by 90 degree domain reorientation.

Relaxor-type ferroelectric (1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3 (PMN-PT) films, 2-3 mum in thickness, with a PbTiO3 content (x) ranging from 0 to 1 were grown on [(100).sub.c]SrRuO3 ll (100)SrTiO3 substrates at 650 degree Celsius by metal-organic chemical vapor deposition. The constituent phase changed from a rhombohedral (pseudocubic) single phase, a mixture phase of rhombohedral (pseudocubic) and tetragonal phases, and a tetragonal single phase, with increasing x.

Relaxor-type ferroelectric (1-x)Pb(Mg1/3Nb2/3)O3-xPbTiO3 (PMN-PT) films, 2-3 mum in thickness, with a PbTiO3 content (x) ranging from 0 to 1 were grown on [(100).sub.c]SrRuO3 ll (100)SrTiO3 substrates at 650 degree Celsius by metal-organic chemical vapor deposition. The constituent phase changed from a rhombohedral (pseudocubic) single phase, a mixture phase of rhombohedral (pseudocubic) and tetragonal phases, and a tetragonal single phase, with increasing x.

A heteroepitaxial PbZr(sub 1-x)Ti(sub x)O3 (PZT) thin film was fabricated by means of hydrothermal epitaxy at 210 degree Celsius below Curie temperature without undergoing the paraelectric to ferroelectric phase transition. From transmission electron microscope and piezoresponse force microscope observations, it was confirmed that the fabricated PZT thin films had only a-c monodomain without an 'a' domain in the as-synthesized state.

A methodology is presented to extract the relevant quantities of a Schottky contact, in the specific case of metal-ferroelectric-metal structures, by using the metal-ferroelectric interface. The models are applied to Pb(Zr, Ti)O3 thin films with different Zr/Ti ratios, fabricated by different deposition methods and having different Schottky contacts.

Phases and domains in a (110)-cut Pb(Mg1/3Nb2/3)(sub 0.74)Ti(sub 0.26)O3 single crystal are investigated as functions of temperature and dc electric (E) field by dielectric permittivity, polarizing microscopy and electric polarization. The unpoled sample has a dominant rhobohedral (R) phase, which coexists with monoclinic (M) phase domains at room temperature.

The time-dependent effects of a commercial soft lead zirconate titanate material are investigated at room temperature. The results help in understanding the mechanism of creep effects that might provide contributions to improve the performance and reliability of ultrahigh-precision positioning piezoactuators.

The nanocrystalline Pb(sub 0.92)Nd(sub 0.08)(Zr(sub 0.53)Ti(sub 0.47))(sub 0.98)O(sub 3)(PNZT) is synthesized by high-energy ball milling (mechanical alloying). The analysis of impedance and dielectric properties of PNZT as a function of temperature has showed the high permittivity of 10626 at 10 kHz at the Curie temperature (Tc), broadening of permittivity peak, lowering of Tc, decrease in conductivity and increase in relaxation time with the decrease in crystalline size.

The effect of oxygen content in the sputtered Pt oxide (Pt(sub x), x = 0.4 to 1) top electrode suppressing the hydrogen degradation of ferroelectric capacitors of PbZr(sub 0.4)Ti(sub 0.6)O3 (PZT) and also the role of hydrogen in degradation of ferroelectric capacitors are investigated. The results show that the high oxygen content in PtO(sub x) electrode interrupts the catalytic reaction of Pt in dissociation of hydrogen molecules and suppresses the interfacial segregation of hydrogen and its incorporation with PZT.

A systematic study of the optoelectronic processes occurring in composites made of near-infrared (IR) emitting nanocrystals and conjugated polymers are reported. Results reveal that the process responsible for quenching the visible luminescence of the polymer by the nanocrystal varies depending on the nanocrystal composite.

Temperature dependences of the optic phonons in PbSc1/2Ta1/2O3 (PST) sol-gel films deposited on sapphire substrate are studied by means of Fourier transform far-infrared transmission spectroscopy in the temperature range of 20-900 K. In all the four films displaying different B-site order, the transverse-optic (TO) mode near 80 cm(super -1) at 10 K softens on heating to approximately 45 cm(super -1).

The dielectric behavior of Pb0.5Ca0.5TiO3 thin films with different thickness is measured using capacitance versus voltage (C-V) technique. The feasibility of the films for fabrication of voltage tunable capacitors and charge storage devices (DRAMs) is confirmed.

The effects of constant bias stress and electric field on the electromechanical behavior of -oriented Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 (PMN-0.32PT) relaxor ferroelectric single crystals are examined. The phase-transformation-induced polarization rotation through intermediate phases can be used to explain the observed effects of bias stress and bias electric field on the electromechanical properties off -oriented PMN-0.32PT single crystals.

The long-range order (LRO) parameter (S) of single isolated L1(sub 0)-FePd nanoparticle is obtained by quantitative analysis of nanobeam electron diffraction (NBD) intensities and intensity calculations considering the multiple scattering of electrons. The lattice parameter, the alloy composition, and the particle thickness, which are useful in the LRO parameter determination, are evaluated by transmission electron microscopy.

Raman spectroscopy is used to analyze the local symmetry breaking in Pb(sub x)Sr(sub 1-x)TiO3 (PST) ceramics and composites to eliminate all the effects but grain boundaries. The results show a clear evidence for the existence of polar regions localized mostly at grain boundaries.

The influence of grain size on phase composition and electrical properties is evaluated in relaxor ferroelectric system Pb(Ni1/3Nb2/3)O3-Pb(Zr,Ti)O3 (PNN-PZT) near the morphotropic phase boundary. Observations reveal that increasing the sintering temperature leads to grain growth in the PNN-PZT with a grain growth exponent of n=3 and the ferroeletric behavior depends on grain size and phase composition.

Acoustic emission (AE) method is used to determine the electric-field-induced-phase transition in the relaxor Pb(Mg1/3Nb2/3)O3 (PMN). It is revealed that the AE method is a very powerful method for the study of nonergodic systems such as PMN and the comparison with other methods has provided an interesting insight on the local and long-range polar order of PMN.

A study is carried out on the dielectric properties and domain structure that is measured as functions of temperature in a (001)-oriented Pb(Mg(sub 1/3) Nb(sub 2/3))(sub 0.65)Ti(sub 0.35)O(sub 3) (PMNT35%) single crystal with and without a prior dc electric (E)-field poling. Details of the phase thermal stability of (001)-cut PMNT35% crystal with and without a prior dc E-field application along [001] are revealed.

A study was carried out on the extrinsic contributions to the dielectric response of 0.5Pb(Yb1/2Nb1/2)O3-0.5PbTiO3 thin films with (100) or (111) crystallographic orientation. The findings of the study shows that (100) oriented films show a slightly higher extrinsic contribution to their dielectric behavior than (111) oriented films.

A study was conducted by growing Fe-doped 0.62Pb(Mg1/3Nb2/3O3-0.38PbTiO3 (PMN-0.38PT) single crystals with two different dopant concentrations, 0.2 and 1.0 mol % with the help of a modified Bridgman technique. Examination of the effect of Fe substitution on dielectric and pyroelectric properties was done.

A study is carried out to evidence a hysteretic, irreversible electric-field-induced transition to a quasimonodomain rhombohedral phase in [111]c-oriented, pseudo-orthorhombic PZN-8PT [0.92Pb(Zn1/3Nb2/3)O3-00.8PbTiO3]. This study is carried out by using strain-field measurements and in situ polarized light microscopy.

The dependence of the domain structure on poling for (001)-oriented Pb(Mg1/3Nb2/3)O3-x%PbTiO3 crystals is discussed by scanning force microscopy in the piezoresponse mode and by polarized optical microscopy. The results demonstrate a domain hierarchy on various length scales, ranging from nanometers to millimeters, which is notably dependent upon the electrical history of the specimen.

The complex solid solution (1-x)Bi(Mg(sub 3/4)W(1/4)O(sub 3)-xPbTiO(sub 3) [(1-x)BMW-xPT] was investigated by building the ferroelectric family based on the Bi[Mg(super +3)O(sub 3)-PbTiO3 solid solutions. The phases and basic dielectric properties in a (1-x)Bi(Me'Me')O(sub 3)-xPbTiO(sub 3) system and preliminary structural phenomena are reported.

A study is carried out on the crystal structure and dielectric properties of (1-x)Pb(Yb1/2Nb1/2)O3-Pb(Sc1/2Nb1/2)O3 (PYN(1-x)PSNx) (O less than or equal to x less than or equal to 0.60) solid solution. Details of its pseudobinary phase diagram are determined.

Planar-impact experiments with ferroelectric ceramic were conducted on a gas-gun facility to determine Hugoniot states, to examine constitutive mechanical properties during shock propagation, and to investigate shock-induced depoling characteristics. Details of the shock wave compression of poled Pb(sub 0.99)(Zr(sub 0.95)Ti (sub0.05))(sub 0.98)Nb(sub 0.02)O(sub 3) results in rapid depoling and release of bound charge were discussed.

Temperature and field dependent investigations of the longitudinal electromechanical properties of [001]- and [110]- oriented 0.955Pb (Zn(sub 1/3)Nb(sub 2/3))O(sub 3)-0.045PbTiO(sub 3) single crystal are performed. Electromechanical equivalence was found between [001] and [110] orientations in the ferroelectric rhombohedral Fe(sub r) phase region, but not in the ferroelectric tetragonal Fe(sub t).

The solid solution between the normal ferroelectric Pb(Zr(sub 1/2)Ti(sub 1/2))O(sub 3) (PZT) and relaxor ferroelectric Pb(Ni (sub 1/3)Nb(sub 2/3))O(sub 3) (PNN) was synthesized by the columbite method. The transistor between relaxor to normal ferroelectricity was typified by a quasilinear relationship between the diffuseness parameter Delta (sub gamma) and PZT mole fraction x.

Ferroelectric domain structures of a (001)-oriented lead magnesium niobate-lead titanate tetragonal crystal is examined under cyclic bipolar electric fields. The model based on 180 degree domain switching is suggested to explain interpenetration of the domains and the withdrawal of the original domain walls.

Pb(sub 1.2)Sr(sub 1-x)Ti(sub x)O(sub 3) (PZT) films with a variety of compositions were prepared by spin coating on Pt/Ti/SiO(sub 2)/Si substrate with sol-gel processing. The roles of composition (phase) and orientation in ferroelectric properties of PZT films are determined and the (111)-oriented films have larger remanent polarization n and coercive field than the (100)-oriented films for both Zr-rich PZT(65/35) and Ti-rich PZT(35/65) compositions.

The findings of dielectric studies are correlated with structural changes in [(Pb(sub 1-x)Ba(sub x))ZrO(sub 3) (PBZ), (x=0.05)] PBZ05 and PBZ10 (x=0.10) using high temperature x-ray diffraction (XRD). The results of high temperature XRD studies for the AFE to FE transition in PBZ05 shows a wide coexistence region (~80degreeC) and a large transformation volume change (~0.8%) confirming the strongly first order character of this transition.

Polarization reversal and domain dynamics are investigated in 0.7Pb(Mg(sub 1/3)Nb(sub 2/3))O(sub 3)-0.3PbTiO(sub 3) using a method of current transients. The kinetics of the transients are modeled to an equation of state for heterogeneous nucleation in the vicinity of random fields.

High oriented lead-zirconium-titanate (PZT) thin films are grown by reactive rf-magnetron sputtering using multielemental metallic targets and the effects of deposition parameters on the film composition and texture evolution are established. The partial pressure of oxygen [O(sub 2)] and the heating rates during postdeposition anneal are identified as critical parameters for the growth of highly oriented (111) and (100) PZT films.

Experimental studies of the lifetime and reproducibility of the Pb(Zr, Ti)O3(PZT) ceramic ferroelectric cathode with high current density is reported. A lifetime of lead zirconate-titanate ceramic cathode with composition related to a ferroelectric phase is examined.

Strong influence of the lanthanum (La) admixture added to the lead-barium-zirconate-titanate (PBZT) ceramics of a chosen composition (Ba/Zr/Ti-25/70/30) on grain structure, electric conductivity, dielectric, and pyroelectric properties are reported.

X-ray diffraction data is presented by demonstrating after high field poling, solid solutions of lead zinc niobate with 8% lead titanate (PZN-PT) consisting of mixture of a dominant monoclinic phase and a remnant tetragonal phase. Diffraction shows a slight distorted version of the rhombohedral zero field solution resulting from the domain walls that consist of a tetragonal phase.

The two-dimensional spatial distribution of the composition of the deposit was experimentally studied and analyzed by using the sorption approach. Results show a good agreement between the experimental and sorption analysis, and suggest a determining role of the plume-substrate interaction in the deposition process.