Defect Morphology of GeSe_xTe_1−x Single Crystals grown by physical vapor transport

Abstract

Slip lines and bands, mosaic patterns, dislocations, and twins, produced by the atom displacement type phase transformation from the cubic (high T) to the rhombohedral (room T) modification of GeSexTe1−x single crystals (x = 0.1–0.4), were observed by chemical etching, microscopic, and Laue X‐ray back reflection techniques. Structural defects increase with Se content of the crystals. Post‐growth annealing improves the crystal morphology. Vacancy clusters in Ge0.49 (SexTe1−x)0.51 (x = 0.1, 0.2) are Ge vacancies.