Observation, morphology evolution and elimination of Cd inclusions in indium-doped CdZnTe single crystals

In this paper, several interesting kinds of Cd inclusions were observed in indium-doped CdZnTe (CZT:In) crystals. Characterizations revealed that all inclusions were actually clusters of many irregular Cd precipitates with a size lower than 1 μm. The needle-like Cd inclusion only had three orientations (121), (211) and (211) along which dislocations and stacking faults lie. The cross-like Cd inclusion consisted of two crossed needle-like inclusions with a 120°included angle. And the star-like Cd inclusion consisted of three crossed needle-like inclusions with a 120°included angle to each other. The mechanism of morphology evolution of Cd inclusions is proposed for the first time. Moreover, all kinds of Cd inclusions could be completely eliminated by appropriate post-growth annealing under a Te atmosphere.