Microtexture studies of PST and PZT ceramics and PZT thin film by electron backscatter diffraction patterns

Abstract

Crystallographic orientations of twelve different lead scandium tantalate (PST) ceramics, two lead zirconate titanate ceramics (PZT) and one PZT thin film were investigated by the technique of electron backscatter diffraction (EBSD) in the scanning electron microscope. The PST ceramics were processed under different conditions of temperature and annealing. Crystal orientations in the bulk ceramics were examined and the results were plotted in microtexture pole- and inverse pole-figures. Local texture and misorientation between adjacent grains in certain selected regions of the ceramics were also examined. To compare the results of the PST with another lead-based ferroelectric material, an unpoled and a poled PZT ceramics were studied for their texture. The electrical and electromechanical properties of the PZT ceramics were also measured in an attempt to correlate texture with properties. Extensive studies revealed insignificant texture in the ceramics, indicating no relationship between ferroelectricity and texture. Preferred orientations were observed in a PZT thin film grown by pulsed-laser deposition (PLD) method. Though improved anisotropy in PZT thin films can be attributed to texture, there is no indication of the dependence of piezoelectricity on texture.