Investigation of Te inclusion induced glides and the corresponding dislocations in CdZnTe crystal

Abstract

Te inclusion induced dislocations were identified using FE-SEM imaging on CdZnTe (111) B face, after etching by Everson solution. Hexagram etching pits rosette was observed, which suggests a noticeable enrichment of dislocations surrounding a Te inclusion. The spatial distribution of the etch pits possibly correlates with the screw and edge dislocations, respectively. The corresponding dislocations attributed to the tetrahedral and tangential glide, respectively, occurred by local deformation of CdZnTe crystal. This deformation was contributed by the contraction of Te inclusions during cooling down to room temperature, since the thermal expansion coefficient of Te is significantly higher than that of CdZnTe crystal. Both tetrahedral and tangential glides were dominated by the plastic deformation mechanism for zinc-blende structure material. In addition, the volume of the dislocation enriched region was found to be significantly bigger than the volume of Te inclusion itself, and was proportional to the volume of the originating Te inclusion.