Upgrading of CdZnTe by annealing with pure Cd and Zn metals

A method for the annealing of a CdZnTe crystal is described in this paper. Pure Cd and Zn metals are used as annealing sources, which simultaneously provide exact Cd and Zn equilibrium partial pressures for CdZnTe at a certain temperature. Characterizations reveal that homogeneity is highly improved and the defect densities are decreased by more than one order, and hereby the structural, optical and electrical properties of the CdZnTe crystal are evidently improved by this annealing. Investigation of the temperature dependence of the CdZnTe quality after annealing shows 1073 K to be the preferable annealing temperature for CdZnTe. This annealing process has already been demonstrated to be superior to approximate equilibrium partial pressure annealing by using Cd_1-yZn_y alloy as the annealing source.