<title>Interaction between the domain walls and the structural defects in BaTiO<formula><inf><roman>3</roman></inf></formula> crystals</title>

Abstract

Investigations of the domain structure and the defect structure of single crystals were carried out by optical and electron microscopy. Peculiarities and relationships between the defect structure and the domain structure were revealed. It has been found that dislocations in a form of tristetrahedron projections appear on the surface and thermal treatment increases density of such dislocations in the crystal. The complex domain structure consisting in: (1) regions exhibiting different domain structure features, (2) metastable 90° a -a -domains with the substructure of the backward domains; (3) dense a -c -domain series; and (4) blocks exhibiting preferred orientation of positive domain edges on the surface was found. It has been stated that crystals poled at room temperature exhibit different surface reliefs on the opposite etched surfaces. It has been found that the surface layer of BaTiO3 crystal often exhibits the domain structure, which differs from the structure inside the crystal. Most often the c -domain surface layer exists on crystals exhibiting both simple and complex domain structure. However, the domain structure inside the crystal has an effect on the character of distribution and orientation of 180°D domain walls in the surface layer. Contribution to better understanding of electrical properties of real BaTiO3 crystals was done.© (2003) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.