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Rhombohedral Pb(Zr0.70Ti0.30)O-3 thin films of four different well-defined textures, namely, (100), (111), bimodal (110)/(111), and (100)/(111), were prepared by a sol-gel method. The films were characterized in terms of grain size, presence of second phases, surface roughness, columnarity of grains, and other microstructural features. The dielectric, ferroelectric, and fatigue properties were investigated, with emphasis on the hysteresis switching characteristics. Results are discussed from the reference p

Pyrochlore free 0.9Pb(Mg1/3Nb2/3)O-3-0.1PbTiO(3) thin films were prepared from alkoxide-based solution precursors. Preferential (111) crystallographic orientation was obtained on TiO2/Pt/TiO2/SiO2/Si substrates by spin coating. Dielectric, electrostrictive, and piezoelectric properties of the films were characterized in detail. Films show relaxor-like behavior, but with dielectric permittivity which is low (around 4300 at peak and at 340 Hz with E-ac=1.6x10(6) V/m) compared to bulk ceramics and single cryst

Lead oxide based ferroelectrics, represented by lead zirconate titanate (Pb(Zr,Ti)O-3) or PZT) are the most widely used materials for piezoelectric actuators, sensors and transducers due to their excellent piezoelectric properties. Considering lead toxicity, there is interest in developing piezoelectric materials that are biocompatible and environmentally friendlier. The low density of non-lead based materials can also be an advantage in transducers for underwater and medical imaging due to expected lower a

Leakage conduction of (Pb, La)(Zr, Ti)O-3 (PLZT) films grown on Pt bottom electrode, with Pt and Pt/SrRuO3 (Pt/SRO) top electrodes is studied. It is found that the conduction behavior of the ferroelectric capacitors strongly varies depending on the degree of interdiffusion from the electrode into the ferroelectric material. If the diffusion is limited, the conduction properties of the Pt/SRO/PLZT/Pt capacitor are similar to that of the conventional Pt/PLZT/Pt system. For the opposite case of excessive inter

The integration of ferroelectric polymer gates on a Mn-doped GaAs magnetic channel provides a promising route for the persistent field-effect control of magnetic properties in high-quality diluted magnetic semiconductors (DMSs) that are otherwise incompatible with traditional oxide ferroelectrics. That control demands the thinnest possible DMS layers, for which to date the Curie temperature (T-C) is severely depressed. Here we show that reducing the channel thickness from 7 to 3-4 nm by etching, followed by

The dielectric response of ferroelectric-dielectric composites is theoretically addressed. Dielectric permittivity, tunability (relative change of the permittivity driven by dc electric field), and loss tangent are evaluated for various composite models. T ...

Piezoelectric response nonlinearity is approached using the Preisach description of hysteretic systems as collection of distributed bistable units. The Preisach model and its recent physical interpretation in terms of moving domain wall in a stochastically described pinning field are reviewed. It is shown that such an approach can effectively render not only the piezoelectric coefficient field dependences but also the field-response hysteresis, especially in the well-known case of linear piezoelectric field

The effects of donor (Nb, Ta) and acceptor (Na, Mg, Fe) dopants on the crystallization mechanism of PZT thin films were investigated. The parameters which control microstructure development were found to be different for donors and accepters. Lead stoichiometry was found to be the critical parameter for donor doped films. Donor substitutions in the perovskite lattice ABO(3), require a compensation by creation of A-site vacancies, Pb1-x/2(Zr,Ti)(1-x) NbxO3, in order to maintain electroneutrality. In the pyro

Complex perovskite A(B'B'')O3 ceramics with various degrees of B-site order have been structurally and spectroscopically characterized by means of x-ray diffraction, transmission electron microscopy, and infrared reflectivity. In Ba(Fe1/2Nb1/2)O3 and Pb(Fe1/2Nb1/2)O3, no order could be detected whereas Pb(In1/2Nb1/2)O3, Pb(Mg1/3Nb2/3)O3, and Pb(Sc1/2Ta1/2)O3 (unannealed) all exhibited weak reflections associated with small ordered regions Pb(SC1/2Ta1/2)O3 was also prepared by appropriate heat treatment in t

Several bottom electrode systems for ferroelectric thin film deposition onto reactive substrates or reactive metal films have been investigated with respect to chemical barrier properties and contact resistivity. Such electrode systems should not deteriorate by oxidation, and should prevent oxygen diffusion into the underlying base metal. First, the protective performance of Pt, Ru, RuO2/Ru, and Cr has been evaluated on reactive substances such as W, Zr, Mo, and TiN; On most materials, a reactive and passiv

The dielectric behavior and structure of the Sr(Zn1/3Nb2/3)O3-Ba(Zn1/3Nb2/3)O3 solid solution have been investigated with the intention of understanding the relationship between the structural changes and the temperature coefficient of the relative permittivity tau(epsilon). A correlation between the value of tau(epsilon) and the occurrence of O-octahedra tilts has been established. The occurrence of ferroelastic domains and their influence on tau(epsilon) has also been investigated. It is proposed that the

Fatigued state of the Pt-PZT-Pt system is studied by means of low-temperature conduction measurements. It is shown that the conduction in the temperature interval of 100-140 degrees K is determined by the cold field emission of electrons (tunneling conduction mechanism). The Fowler-Nordheim equation describes well the observed current-voltage relations for reasonable values of the system parameters. The conduction measurements in this regime show that the strong fatigue of the switching polarization provoke

A silicone-based one-transistor nonvolatile memory cell has been implemented by integration of a ferroelectric polymer gate on a standard n- type metal oxide semiconductor field effect transistor. The polarization reversal in the gate results in a stable a ...

The transverse piezoelectric coefficient (d(31)(star)) has been calculated for tetragonal barium titanate (BT) and lead titanate (PT) cut along nonpolar axes, over a range of temperatures, using the phenomenological Landau-Ginzburg-Devonshire theory. It is ...

Antiphase boundaries (APBs) are unique domain walls that may demonstrate switchable polarization in otherwise non-ferroelectric materials such as SrTiO3 and PbZrO3. The current study explores the possibility of displacing such domain walls at the nanoscale ...

The postresonator method proposed by Hakki and Coleman for the measurement of dielectric properties of solids in the microwave region is reexamined. Based on the experiments performed around 10 GHz, the limitations of the method in loss determination for materials with tan delta < 5 x 10(-4) are outlined. Alternative techniques for studying high-Q materials are described. Loss measurements performed on well-prepared ceramics have been used to draw comparisons among these techniques. Some of the experimental

Transparent single crystals of Pb(Zn-1/3, Nb-2/3)O-3-PbTiO3 (PZN-PT) perovskite have been grown by the slow cooling method in a temperature gradient furnace. The optimization of growth techniques to crystallize PZN-PT with a cubic habitus is described in details. The growth temperature range and cooling rates was carried out in different lead fluxes, Crystal recovery from the residual flux was obtained by different techniques based on liquid flux elimination at the end of the growth process. The best transp

Electromechanical properties of a number of ferroelectric films including PbZrxTi1-xO3(PZT), 0.9PbMg(1/3)Nb(2/3)O(3)-0.1PbTiO(3)(PMN-PT), and SrBi2Ta2O9(SBT) are investigated using laser interferometry combined with conventional dielectric measurements. Effective electrostriction coefficients of the films, Q(eff), are determined using a linearized electrostriction equation that couples longitudinal piezoelectric coefficient, d(33), with the polarization and dielectric constant. It is shown that, in PZT film

A zero-field spontaneous relaxor-ferroelectric transition is reported in Pb(Sc0.5Ta0.5)O3 (PST). This behavior is different from that of other relaxors, where such transitions occur only under the field. A highly disordered PST that has the wide relaxation spectrum typical of relaxors is shown to transform spontaneously into a macroscopic ferroelectric state. Introduction of defects (lead vacancies) into the material impedes the transition resulting in the usual relaxor behavior. Dielectric properties of PS

Micro-Raman spectroscopy is a convenient tool to probe individual objects with a feature size on the submicron scale. The phase, composition, and orientation of Pb(Zr,Ti)O-3 fibers fabricated via hydrothermal processing have been characterized by this tech ...

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Influence of texture on the switching behavior of Pb(Zr0.70Ti0.30)O3 sol-gel derived thin films

Dielectric and electromechanical properties of ferroelectric-relaxor 0.9 Pb(Mg1/3Nb2/3)O-3-0.1PbTiO(3) thin films

Lead free piezoelectric materials

Control of leakage conduction of high-fatigue-endurance (Pb, La)(Zr, Ti)O-3 film ferroelectric capacitors with Pt/SrRuO3 electrodes

Enhanced Curie temperature and nonvolatile switching of ferromagnetism in ultrathin (Ga,Mn)As channels

Ferroelectric-dielectric tunable composites

Preisach modeling of piezoelectric nonlinearity in ferroelectric ceramics

Effect of dopants on the crystallization mechanism of PZT thin films

B-Site Order and Infrared Reflectivity in a(B'b'')O3 Complex Perovskite Ceramics

Conducting barriers for direct contact of PZT thin films on reactive substrates

Effect of Structural-Changes in Complex Perovskites on the Temperature-Coefficient of the Relative Permittivity

Tunneling conduction in virgin and fatigued states of PZT films

Retention in nonvolatile silicon transistors with an organic ferroelectric gate

Correlation between dielectric anisotropy and positive or zero transverse piezoelectric coefficients in perovskite ferroelectric single crystals

Moving antiphase boundaries using an external electric field

Dielectric measurements on high-Q ceramics in the microwave region

Growth and properties of transparent Pb(Zn-1/3, Nb-2/3)O-3-PbTiO3 single crystals with a cubic habitus

Characterization of the effective electrostriction coefficients in ferroelectric thin films

The Spontaneous Relaxor-Ferroelectric Transition of Pb(Sc0.5ta0.5)O3

Analysis of composition homogeneity and polarization orientation of PZT submicron fibers by micro-Raman spectroscopy