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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 structure of chemically ordered regions in Zr-doped Pb(Mg(sub 1/3)Ta(sub 2/3))O3 is studied by means of transmission electron microscopy (TEM). The addition of 5-mol percent PbZrO3 leads to the formation of large coherent ordered domains, which were perfectly suitable for the investigation by TEM.

The perovskite system exhibits a large piezoelectric coefficient and a high Curie temperature in the vicinity of the morphotropic phase boundary. The present contribution reports on revisions to the BiScO3-PbTiO3 phase diagram.

The effects of a decreasing top electrode size on the electric and piezoelectric properties of tetragonal Pb(Zr(sub x), Ti(sub 1-x))O(sub 3) thin films were investigated. Both propertied were found to decrease rapidly with decreasing size of the used Pt top electrode for the investigated dimensions of 5 mm to 100-mu m edge length.

The pyroelectric coefficients of many single crystals, oriented and poled along three different crystallographic directions were measured using a dynamic method. For each composition and orientation, two different poling procedures were compared.

The (100)-highly oriented LaNiO3 buffer layers were grown and the highly (100)-oriented PbZr(sub 1-x)Ti (sub x)O(sub 3) thin films with various compositions were obtained on them. The misfit elastic strains were found to be critical factors to determine the orientation of PZT thin films.

A detailed investigation on the dielectric anomalies in [111] oriented PZN-4.5 percent PT single crystals induced by different levels of bias electrical field during temperature variations is reported. It is concluded that the amplitudes of the dielectric anomalies are frequency dependent, but the critical temperatures are practically independent of the field strength.

Ferroelectric copper(II)-modified polycrystalline Pb[Zr0.54Ti0.46]O3 ceramics with a dopant concentration of 0.25 mol percent were investigated by means of electron paramagnetic resonance and hyperfine sublevel correlation spectroscopy. The results prove that copper is incorporated at the octahedrally coordinated [Zr,Ti] site, acting as an acceptor and disfavor a directly coordinated oxygen vacancy to the copper center for charge compensation.

The temperature dependence of the current conduction mechanisms in Au/Pb(Zr(sub 0.53), Ti(sub 0.47))O(sub 3)/ Pt(aU/PZT/Pt) metal-insulator-metal thin film capacitors is investigated. It is found to be a promising material for large-scale integrated circuit applications.

Epitaxial Pb(Zr(sub x)Ti(sub 1-x)O3 (PZT) thin films with various x values are prepared on single-crystal substrates, and changes in electrical properties with x value and crystal orientation are systemically investigated. The results suggested that the electrical properties of epitaxial PZT thin films strongly depend on both of the composition and orientation of the films.

X-ray diffraction and photoelectron spectroscopic studies of (001)-oriented Pb(Zr0.52Ti0.48)O3 thin films prepared by laser ablation is presented. Findings show that oxygen pressures higher than 200 mTorr during the deposition of PZT thin films appear to favor the growth of stoichiometric PZT thin films.

Epitaxial PbTiO3 films of various thicknesses are prepared on a Pt(001) bottom electrode layer, which is also grown epitaxially on MgO(001) single crystal substrates. The findings show that as the film thickness increased, relaxation of the initial compressive misfit stress was enhanced, reducing the initial c-domain abundance.

Crystalline solutions of (1-x)(Bi,La)(Ga0.05Fe0.95)O3-xPbTiO3 (BLGF-PT) are fabricated with La concentrations of 0,10, and 20 at. %. The results demonstrate that BLGF-PT is a competitive alternative piezoelectric material to Pb(Zr,Ti)O3 with reduced lead content.

The dielectric and structural properties of Bi(Ga(Sub x)Fe(Sub 1-x))O3-PbTiO3 (BGF-PT) crystalline solutions are investigated. The study develops a BGF-PT material with values of K >400 and tan delta

The binding of the lead (II) cations to the terpyridine-type subunits of the helical ligand is examined. It is found that it leads to the self-assembly of different polynuclear metallosupramolecular architectures of nanometric size.

The electronic conductivity of PbS and CdTe nanoparticle monolayers was examined voltammetrically by using interdigitated array (IDA) electrodes at the air/water interface. The conductivity of the final interfinger deposits was about two orders of magnitude smaller than that for pure metallic lead, indicating some surface contamination and/or less than perfect crystalline structure.

Offsets of the hysteresis loops along the polarization axis have been observed on a step graded Pb(Zr,Ti)o(sub 3) (PZT) thin film using a sawyer-Tower (ST) circuit. Artificial shifts of hysteresis loops were observed on a nongraded PZT film using a ST circuit, providing the flow of asymmetrical conduction currents is intentionally provoked. This raveled that offsets observed on GFDs may represent a dc voltage V(sub off).

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 results indicate the considerable effect of polydomain structure and its stability as a function of external field in these highly textured polycrystalline PZT films.

The heterostructures of perovskite PbSc(sub 0.5)Nb(sub 0.5)O3 (PSN) thin films were fabricated by pulsed laser deposition and their relaxor and normal ferroelectric behavior were studied in a broad range of temperatures and frequencies. The evolution of behavior and shift of dielectric maxima are found to correlate with the temperature of deposition and the type of the substrate, which was suggested to refer to the microstructural factors such as in-plane strain, grain size, and misfit dislocations.

Anelastic behavior in lead zirconate titanate ceramic by internal friction, three important peaks were observed. Upon application of the driving field, the onset of extrinsic electromechanical response was found to follow the stretched exponential relaxation pattern.

Unipolar electric field-induced strain was studied in the [100]cub oriented 0.65Pb(Mg(sub 1/3)Nb(sub 2/3))O(sub 3)-0.35PbTiO(sub 3) crystals with composition close to the morphotropic phase boundary, which is known to show enhanced piezoelectric properties. The domain of the tetragonal phase with polarization perpendicular to the poling field was observed.

The structural modifications in the films were studied using x-ray diffraction and micro-Raman scattering techniques. Raman spectra exhibited characteristic features of pure PbTiO(sub-3) thin films.

The graphical peak analysis method (discharge current transient spectroscopy (DCTS)) is proposed and tested for determining the electrically active traps with close emission rates in thin insulator films. Experimentally it has been show that DCTS can determine the densities per unit area and emission rates of traps with five close emission rates in Pb(Zr, Ti)O3 (PZT) thin films.

The perovskite structure of PZN ceramics was stabilized by the addition of a Ti-rich side tetragonal PZT after sintering at 1100 degrees C. When 40 % PZT was added, a rhombohedral perovskite phase was formed without any trace of the pyrochlore phase.