TEM Study on Defects in Epitaxial CdZnTe Films Deposited on (001)GaAs by Close-Spaced Sublimation

Abstract

ABSTRACTA transmission electron microscopy (TEM) study on defects in a 30 μm-thick epitaxial CZT film deposited on (001)GaAs via close-spaced sublimation was performed. The epi-layer is of good quality without twins. Dislocations and stacking faults are mainly gathered near the interface. The dislocations are extrinsic either of Lomer edge or 60° type. Pseudo extrinsic stacking faults consisting of two independent and oppositely oriented extrinsic dislocations have been found both on the (111) and the $(\bar 1\bar 11)$ planes. L-shaped defects originated from the interface have been discovered. The near-interface-side of L is consisted of 3 compressed (111) planes and the lateral side is consisted of 3-4 misarranged $(\bar 1\bar 11)$ planes. This L-shaped defect is induced by the absence of a misfit dislocation at the intersection between L and the interface.