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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.

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.

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.

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 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.

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 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 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.

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.

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.

The spatial variation of ferroelectric properties with submicron lateral resolution is presented by using an AFM piezoelectric measurement technique. The phase images obtained through this technique represents the polarization direction, while contrast in the amplitude images shows the spatial variation in d33.

X-ray diffraction measurements are used for investigating the magnetic and dielectric properties and the magnetoelectric effect of ceramics with a composition of in multiferroic Pb(Zr, Ti)[O.sub.3]-LaMn[O.sub.3] composites. The reduction in spontaneous magnetization is attributed to the change in hole concentration around the boundaries of the precipitated ferromagnetic (La, Pb)Mn[O.sub.3] grains and the resultant decrease of ferromagnetic Curie temperature.

Numerous studies are used to investigate the polarization fatigue suppression behavior of the ferroelectric [Pb.sub.1-x][Ba.sub.x]([Zr.sub.0.52][Ti.sub.0.48])[O.sub.3] (PBZT) thin films, prepared by the sol-gel method. The results reveal that Ba doping of the substances leads to enhanced ion stability and suppressed oxygen vacancies, which ultimately results in an improved fatigue endurance of the substance.

The determination of the complete set of elastic, piezoelectric and dielectric constants of 0.67Pb([Mg.sub.1/3][Nb.sub.2/3])[O.sub.3]-0.33PbTi[O.sub.3] single crystal is reported using Brillouin scattering. The values of these determined constants are similar to the previously determined four crystal samples by using a hybrid method combining ultrasonic and resonant techniques.

Compositionally-graded (Pb, Ca)TiO3 ferroelectric thin films are prepared by a monoethanolamine-modified sol-gel on platinum-coated silicon substrates using a modified annealing method with 600 degree C annealing temperature. The magnitude of polarization offset displayed a power-law dependence on the electric field, and the direction of the offset depended on the direction of the composition gradient with respect to the substrate.

The fabrication and properties of the porous lead zirconate titanate ceramics with one dimensional ordered pore structure are analyzed. The piezoelectric and dielectric properties of the ceramics are shown to get reduced because of the special structure.

Several studies are conducted to explain the preparation and the size-dependent structural characteristics exhibited by the 0.5[Bi.sub.0.8][La.sub.0.2]Fe[O.sub.3]u0.5PbTi[O.sub.3] solid solutions nanoparticles. A decrease in the particle size is shown to lead to a shift in the crystal structure of the system from tetragonal to rhombohedral.

Lead zirconate titanate (Pb[Zr.sub.0.52][Ti.sub.0.48][O.sub.3]-PZT) thin films with different thicknesses are deposited on Pt(111)/Ti/Si[O.sub.2]/Si substrates by using sol-gel method. The scanning force microscopy is used for studying the effect of thickness on the microscopic piezoresponse and the differences between the macroscopic and microscopic electrical properties of the films are assigned to changes in the nonswitching film-electrode layer and domain structure.

The article presents a newly developed electrostatically tunable magnetoelectric inductor, which is shown to be made of the ring-type Pb(Zr, Ti)[O.sub.3](PZT)/MnZn ferrite compound. The inductor is shown to exhibit high inductance tenability on the application of an electric field of 3 kV/cm.

The magnetoelectric (ME) response and magnetic-field sensitivities of engineered laminate sensors comprised of magnetostrictive and piezoelectric phases are compared. The studies have resulted in the enhancement in the magnetic-field sensitivity for the structures with single crystals and the noise floors are lower for composites with Pb([Mn.sub.1/3][Nb.sub.2/3])[O.sub.3]-PbTi[O.sub.3] (PMN-PT) or Pb([Zn.sub.1/3][Nb.sub.2/3])[O.sub.3]-PbTi[O.sub.3] (PZN-PT) fibers than those with Pb(Zr,Ti)[O.sub.3] (PZT).

The stability of various crystallographic phases of (1-x)BiFe[O.sub.3]-xPbTi[O.sub.3] is studied as a function of composition and temperature. The comparison between the bon lengths between oxygen and other cations has shown that the very high c/a ratio in the tetragonal phase of the system is linked with the covalency effects for bonding between both A and B site cations with oxygen.

The article explains the abnormal dielectric relaxation phenomenon that is normally exhibited by the different Pb[Zr.sub.0.38][Ti.sub.0.62][O.sub.3] multilayers. The results demonstrate that the applied dc bias can be easily employed for changing the dielectric loss of the multilayers.

The article presents a newly devised dc magnetoelectric sensor based on the direct coupling of Lorentz force effect in aluminum strip with transverse piezoelectric effect in 0.7Pb([Mg.sub.1/3][Nb.sub.2/3])[O.sub.3]-0.3PbTi[O.sub.3] single-crystal plate. The applications and the effectiveness of the sensor is also determined.

A sputtering method is used for preparing anatase Nb-based Ti[O.sub.2] transparent conducting oxide on GaN(0001) surfaces. The studies have shown that Nb-doped T[O.sub.2] is a good material for use as transparent electrodes in GaN-based light emitting diodes (LEDs), since reflection at the electrode/GaN boundary is suppressed, enhancing the external quantum efficiency of blue LEDs.

The ferroelectric, dielectric, elastic piezoelectric and electromechanical properties of tetragonal Pb([In.sub.1/2][Nb.sub.1/2])[O.sub.3]-Pb([Mg.sub.1/3][Nb.sub.2/3])[O.sub.3]-PbTi[O.sub.3] (PIN-PMN-PT) crystals are examined. The studies have shown that tetragonal PIN-PMN-P crystals have displayed broader temperature usage range and higher thermal/electric field stability, with improved coercive field and mechanical quality factor in contrast to [001] oriented domain engineered rhombohedral crystals.

The observation of stripe domains in PbTi[O.sub.3] thin films by using standard x-ray diffraction analysis at room temperature is described. The simulations have shown that random variations in size of the domains have affected the separation of the diffuse scattering peaks from that of the specular reflection.

The writing and reading characteristics of ferroelectric domain bits on a preferentially (111)-oriented lead zirconate titanate (PZT) thin film on (111) Pt/Ti[O.sub.2]/Si[O.sub.2]/Si substrate grown by eclipse pulsed laser deposition (PLD) is described. The small roughness of PZT thin films has made a negligible effect on electron force microscope images, which has given the enhanced resolution for the minimum ferroelectric bit size.

The dielectric and ferroelectirc properties of (1-x)Pb([Mg.sub.1/3][Nb.sub.2/3])[(O.sub.3]-(x)PbTi[O.sub.3] ((1-x)PMN-(x)-PT) (x=0.1-0.4) ceramics are measured under compressive stress applied perpendicular to the electric field. The influences of the stress applied in the perpendicular direction to the electric field are opposite to those of the parallel stress.

The phase transition and the phase stability in 0.68Pb([Mg.sub.1/3][Nb.sub.2/3])[O.sub.3]-0.32PbTi[O.sub.3] (PMN-0.32PT) single crystals under different electric fields are examined. The results have helped in understanding the phase transitions as well as the impact of the electric field on the phase transitions in PMN-PT single crystals.

The effect of (Sc,Ta,Ce) doping on the properties of [Bi.sub.3]TiNb[O.sub.9] (BTNO)-based ceramics is examined. The dielectric and piezoelectric properties of [Bi.sub.3][Ti.sub.0.96][Sc.sub.0.02][Ta.sub.0.02]Nb[O.sub.9]-based ceramics have displayed a very stable temperature behavior, along with a high Curie temperature, excellent piezoelectric coefficient and very low temperature coefficient of resonant frequency.

Dielectric and Raman scattering experiments are used for studying polycrystalline [Pb.sub.1-x][Ba.sub.x]Ti[O.sub.3] thin films as a function of temperature. The lack of a well-defined transition temperature and the presence of broadbands in some temperature intervals above the paraferroelectric phase transition temperature have shown a diffuse-type phase transition.

The growth, microstructure and electrical properties of epitaxial PbZr[O.sub.3] films of two different crystallographic orientations, grown on SrRu[O.sub.3]-covered (100)SrTi[O.sub.3] and on BaPb[O.sub.3]-covered and BaZr[O.sub.3]-buffered (100)SrTi[O.sub.3] single crystal substrates, respectively, are described. The studies have shown the antiferromagnetic behavior of the PZO films of both orientations.

The phase instability's role in understanding the piezoelectricity in systems like Pb(Zr, Ti)[O.sub.3] is examined. The results have shown that the phase instability, in contrast with polarization rotation, is responsible for the large piezoelectric properties of systems like Pb(Zr, Ti)[O.sub.3] in the vicinity of the morphotropic phase boundary.

A study was conducted to compute the intrinsic dielectric and piezoelectric properties of single domain, mechanically free, and surface charge compensated PbTi[O.sub.3] nanocrystals (n-Pt) with no depolarization fields, undergoing a finite size induced first order tetragonal->cubic ferrodistortive phase transition. The results showed an anomalous increase in piezocharge coefficients near approximately 15 nm, the critical size for n-Pt.

The nonlinear dielectric properties of 0.9Pb([Mg.sub.1/3], [Nb.sub.2/3])[O.sub.3].0.1PbTi[O.sub.3] (PMN-PT) and Ba[[Ti.sub.0.85], [Sn.sub.0.15]][O.sub.3] (BTS) paraelectrics are investigated. The results have shown that the nonlinear dielectric properties of PMN-PT are higher than that of BTS.

The refractive indices, birefringence, and linear electro-optic (EO) effect of 0.62Pb([Mg.sub.1/3][Nb.sub.2/3])[O.sub.3]-0.38PbTi[O.sub.3] (PMN-PT) single crystals are characterized as a function of wavelength. The two-term Sellmeier dispersion model, in which one oscillator frequency is polarization dependent, is used to discuss the dispersion properties.

An analysis of epitaxial growth of SBN50 ([Sr.sub.0.5][Ba.sub.0.5][Nb.sub.2][O.sub.6]) thin films on SrTi[O.sub.3] single crystal of various orientations is described. The findings revealed an interesting nucleation mechanism of SBN films, the perovskite kernel of the tetragonal tungsten bronze (TTB) structure nucleates first and determines the expitaxial relations with the substrate.

An experiment is conducted to study the fatigue properties of monolithic piezoelectric Pb([Mg.sub.1/3],[Nb.sub.2/3])[O.sub.3]-PbTi[O.sub.3] bilayer composites and study them as functions of piezoelectric-electrostrictive volume fraction (PEVF) ratio. The results thus obtained clearly reveal that the electrostrictive layer highly enhances the fatigue resistance and induce residual stresses in such layers, leading to the partial switching of the domains.

A conventional ceramic processing is used for the preparation of multiferroic laminated composites of Pb[Zr.sub.0.52][Ti.sub.0.48][O.sub.3]/Co[Fe.sub.2][O.sub.4], which is further observed to investigate its dielectric, magnetic and magnetoelectric properties. The analysis reveals that the nature of the PZT and cobalt ferrite (CFO) layers highly influence the properties of such ceramics, which can also be estimated by using the finite-element method.

Lateral size effects of ferroelastic domain structures in epitaxial PbTiO3 thin films are investigated systematically with a viewpoint of misfit strain relaxation mechanism. The results manifest that the domain structure and evolution of the epitaxial thin films could be engineered by the control of misfit strain and its relaxation.

Sols for Pb(Zr0.53Ti0.47)O3 (PZT) thin films were prepared by 2-methoxyethanol route from lead acetate, titanium n-propoxide, and zirconium n-propoxide, the latter either unmodified or modified with acetylacetone or acetic acid in a 2/1 molar ratio and deposited on sapphire (0001). The modification of Zr propoxide with acetylacetone in 2-methoxyethanol results in Zr monomers.

Capacitor over bit line (COB) cell technologies are introduced upon which cell size of 0.937 mu [m.sup.2] at 250 nm minimum feature size technology node is realized based upon ultrathin lead zirconium titanate (PZT) capacitor, current mass-productive one pass transistor and one storage capacitor (ITIC). The new ITIC, COB cell technologies are discussed from which cell size of 0.27 mu [m.sup.2] at 150 nm minimum feature size technology node is realized.

A thermodynamic theory is developed for equilibrium 180 degree stripe domains in ferroelectric thin films on insulating substrates. Such stripe domains form to minimize the energy of the depolarizing field, and lead to a suppression of [T.sub.C] in thin films.

A powerful analytical model for a multilayer circular plate, taking into account the tensile/compressive initial stress of materials, is developed. This model is modified for the study of the piezoelectric constant [d.sub.31] of PZT 54/46 thin film integrated on microscaled circular buckled membranes.

A relaxor-to-normal, or micro-to-macrodomain, transition in Pb([Mg.sub.1/3][Nb.sub.2/3][O.sub.3])-xPbTi[O.sub.3], is found under electric fields applied along [001] for x>=0.24. The results have shown that an intermediate tetragonal ferroelectric phase is important to the sharpness of this transition, as observed in its dielectric response.