OPTICAL, ELECTRON-MICROSCOPIC, AND X-RAY TOPOGRAPHIC STUDIES OF FERROIC DOMAINS IN BARIUM-TITANATE CRYSTALS GROWN FROM HIGH-TEMPERATURE SOLUTION

BaTiO3 single crystals were grown by the top-seeded solution growth (TSSG) technique and the spatial domain configurations in the tetragonal crystals were observed by using a polarizing microscope, SEM, TEM, and X-ray topography. The 90 degrees domain boundaries were stopped, forming wedge shapes, by another 90 degrees boundary. All of the straight lamellar boundaries in the observed domain patterns, even in the herringbone structure, can be interpreted as head-to-tail 90 degrees wads. The irregular overlapped boundary can be observed by using a polarizing microscope and X-ray topography. It looks as if the lamellar domains are penetrating one another because the wedge-shaped lamellar domains are spatially overlapped at those boundaries, After thinning and polishing {001} crystal plates, some 90 degrees a-c boundaries disappear and a-domains become predominant.