Analysis of Grain Boundaries, Twin Boundaries and Te Precipitates in Cd1−xZnxTe Grown bY High-Pressure Bridgman Method

Abstract

AbstractGrain boundaries and twin boundaries in commercial Cd1−xZnxTe, which is prepared by a high-pressure Bridgeman technique, have been investigated with transmission electron microscopy, scanning electron microscopy, infrared-light microscopy and visible-light microscopy. Boundaries inside these materials were found to be decorated with Te precipitates. The shape and local density of the precipitates were found to depend on the particular boundary. For precipitates that decorate grain boundaries, their microstructure was found to consist of a single, saucer-shaped grain of hexagonal Te (space group P3121). Analysis of a Te precipate by selected-area diffraction revealed the Te to be aligned with the surrounding Cd1−xZnxTe grains. This alignment was found to match the (111) Cd1−xZnxTe planes with the (0111) planes of hexagonal Te. Crystallographic alignments between the Cd1−xZnxTe grains were also observed for a high-angle grain boundary. The structures of the grain boundaries and the Te/C1−xZnxTe interface are discussed.