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Ferroelectric Thin Films (ferroelectric + thin_film)
Selected AbstractsLabile Ferroelastic Nanodomains in Bilayered Ferroelectric Thin FilmsADVANCED MATERIALS, Issue 34 2009Varatharajan Anbusathaiah Bilayered Pb(Zr(1,x),Tix)O3 ferroelectric thin film heterostructures show complex ferroelastic nanodomain patterns. These ferroelastic nanodomains exist only in the upper layer, and hence are able to move under the application of an external electric field. Quantitative analysis reveals an enhanced piezoelectric coefficient of ,220 pm V,1, rendering them attractive for a variety of electromechanical devices. [source] Raman Spectroscopy of Ferroelectric Thin Films and SuperlatticesJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 6 2008Dmitri A. Tenne Recent results of Raman spectroscopy studies of lattice dynamics and phase transitions in ferroelectric thin films and superlattices are reviewed. Raman studies of SrTiO3, BaTiO3, and BaxSr1,xTiO3 thin films in comparison with corresponding single crystals are presented; essential differences in the lattice dynamics behavior of thin films and single crystals are discussed. Application of ultraviolet Raman spectroscopy for studies of nanoscale ferroelectric heterostructures, such as BaTiO3/SrTiO3 superlattices, is demonstrated. [source] Effects of Thermal Annealing on the Structure of Ferroelectric Thin FilmsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 4 2006Jiang-Li Cao The effects of thermal annealing on the structure of polycrystalline Pb(Zr0.3Ti0.7)O3 (PZT) ferroelectric thin films prepared by chemical solution deposition on Pt/TiOx electrode stacks were studied using scanning electron microscopy, transmission electron microscopy (TEM), and grazing incidence X-ray specular and diffuse reflectivity of synchrotron radiation. The stratified multilayered structure and element diffusions in the sample were characterized by TEM. Global statistical structural parameters including the density, surface or interface roughness and thickness of each layer in the samples were obtained from fitting the X-ray specular reflectivity using a homogeneous stratified multilayer model of PZT/Pt/TiOx/SiO2. The results showed that the PZT surface and PZT/Pt interface roughness changed slightly during thermal annealing in oxygen at 700°C. By contrast, the density increase of the PZT ceramic and density decrease of the Pt-bottom electrode during annealing were observed. A high density value of the PZT ceramic film after the annealing was found, up to 99.8% of the theoretical value of the corresponding bulk ceramics. The density changes of the PZT and Pt layers were further confirmed by X-ray diffuse reflectivity. The influences of the annealing treatment on the density changes of the PZT and Pt layers were attributed to the further densification of the PZT ceramic and incorporation of light elements such as Zr, Ti and O from the neighboring layers into the Pt layer, respectively, as discussed in correlation with the TEM analyses. [source] Analysis of conductor loss in interdigital capacitor based measurement of dielectric constant of ferroelectric thin filmMICROWAVE AND OPTICAL TECHNOLOGY LETTERS, Issue 3 2008P. Wang Abstract A procedure to include conductor loss in interdigital capacitor based dielectric constant measurements is proposed. The effect of conductor loss and contact resistance can be regarded as a series resistor connected to the interdigital capacitor. If the thickness of the conductor film is known, the conductor loss could be calculated and subtracted from the measurement results. In the frequency range where the dielectric constant of the material in test does not change with frequency, the conductor loss could also be obtained by measuring the frequency dependence of the impedance of the interdigital capacitor. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 566,568, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23141 [source] Influence of substrates on the statical and dynamical properties of ferroelectric thin filmsPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 6 2007J. M. Wesselinowa Abstract Based on the transverse Ising model using a Green's function technique it is shown that the influence of the substrate induces strong changing of various statical and dynamical properties due to different exchange interactions between the ferroelectric thin film and the substrate. Properties such as the phase transition temperature, the polarization, the soft-mode energy, the damping and the dielectric function were found to be highly dependent upon the magnitude and the kind (tensile or compressive) of the stress due to the substrate. There is some competition between the surface and substrate effects. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Quantitative microstructural and texture characterization by X-ray diffraction of polycrystalline ferroelectric thin filmsJOURNAL OF APPLIED CRYSTALLOGRAPHY, Issue 1 2004Jesús Ricote Texture becomes an important issue in ferroelectric materials as it greatly influences the physical properties of polycrystalline films. The use of advanced methods of analysis of the X-ray diffraction profiles, namely quantitative texture analysis or the recently developed combined approach, allows access to quantitative information on the different components of the global texture and to more accurate values of structural and microstructural parameters of both the ferroelectric film and the substrate, not available by more conventional methods of analysis. The results obtained allow important conclusions to be drawn regarding the mechanisms that lead to the development of preferred orientations in thin films and, also, the correlation between them and the ferroelectric behaviour. For example, it is observed that the inducement of a strong ,111, texture component does not mean the complete disappearance of the so-called `natural' ,100,, ,001, components, and that the ratio between the contributions to the global texture of these two components can be changed by the presence of tensile or compressive stress during crystallization of the films. The relative contributions of these texture components are also related to the final properties of the ferroelectric films. [source] Raman Spectroscopy of Ferroelectric Thin Films and SuperlatticesJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 6 2008Dmitri A. Tenne Recent results of Raman spectroscopy studies of lattice dynamics and phase transitions in ferroelectric thin films and superlattices are reviewed. Raman studies of SrTiO3, BaTiO3, and BaxSr1,xTiO3 thin films in comparison with corresponding single crystals are presented; essential differences in the lattice dynamics behavior of thin films and single crystals are discussed. Application of ultraviolet Raman spectroscopy for studies of nanoscale ferroelectric heterostructures, such as BaTiO3/SrTiO3 superlattices, is demonstrated. [source] Effects of Thermal Annealing on the Structure of Ferroelectric Thin FilmsJOURNAL OF THE AMERICAN CERAMIC SOCIETY, Issue 4 2006Jiang-Li Cao The effects of thermal annealing on the structure of polycrystalline Pb(Zr0.3Ti0.7)O3 (PZT) ferroelectric thin films prepared by chemical solution deposition on Pt/TiOx electrode stacks were studied using scanning electron microscopy, transmission electron microscopy (TEM), and grazing incidence X-ray specular and diffuse reflectivity of synchrotron radiation. The stratified multilayered structure and element diffusions in the sample were characterized by TEM. Global statistical structural parameters including the density, surface or interface roughness and thickness of each layer in the samples were obtained from fitting the X-ray specular reflectivity using a homogeneous stratified multilayer model of PZT/Pt/TiOx/SiO2. The results showed that the PZT surface and PZT/Pt interface roughness changed slightly during thermal annealing in oxygen at 700°C. By contrast, the density increase of the PZT ceramic and density decrease of the Pt-bottom electrode during annealing were observed. A high density value of the PZT ceramic film after the annealing was found, up to 99.8% of the theoretical value of the corresponding bulk ceramics. The density changes of the PZT and Pt layers were further confirmed by X-ray diffuse reflectivity. The influences of the annealing treatment on the density changes of the PZT and Pt layers were attributed to the further densification of the PZT ceramic and incorporation of light elements such as Zr, Ti and O from the neighboring layers into the Pt layer, respectively, as discussed in correlation with the TEM analyses. [source] Screen charge transfer by grounded tip on ferroelectric surfacesPHYSICA STATUS SOLIDI - RAPID RESEARCH LETTERS, Issue 2 2008Yunseok Kim Abstract We have investigated polarization reversal and charge transfer effects by a grounded tip on 50 nm thick ferroelectric thin films using piezoelectric force microscopy and Kelvin force microscopy. We observed the polarization reversal in the center of written domains, and also identified another mechanism, which is the transfer of screen charges toward the grounded tip. In order to overcome these phenomena, we successfully applied a modified read/write scheme featuring a bias voltage. (© 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Influence of substrates on the statical and dynamical properties of ferroelectric thin filmsPHYSICA STATUS SOLIDI (B) BASIC SOLID STATE PHYSICS, Issue 6 2007J. M. Wesselinowa Abstract Based on the transverse Ising model using a Green's function technique it is shown that the influence of the substrate induces strong changing of various statical and dynamical properties due to different exchange interactions between the ferroelectric thin film and the substrate. Properties such as the phase transition temperature, the polarization, the soft-mode energy, the damping and the dielectric function were found to be highly dependent upon the magnitude and the kind (tensile or compressive) of the stress due to the substrate. There is some competition between the surface and substrate effects. (© 2007 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] | |||||||||||||