High-resolution electron microscopy of a subgrain boundary in strontium titanate single crystal

Abstract

The microstructure of subgrain boundaries in as-annealed non-doped SrTiO3 single crystals was studied. When the crystal quality is good, it is difficult to observe lattice defects using only transmission electron microscopy (TEM). In such cases, pre-observation by X-ray topography is useful. Hence, the author used both TEM and X-ray topographic techniques. X-ray topographs showed the defect distribution throughout the crystals. [011]-Type crystals generally have subgrain textures. High-resolution transmission electron microscopy revealed that the subgrain boundaries were small-angle tilt boundaries formed by partial dislocations of 1/2(110) Burgers vectors and there were no segregation of impurities.