Purification of Cd0.9Zn0.1Te by physical vapor transport method

In this experiment physical vapor transport (PVT) method had been successfully applied to purify Cd0.9Zn0.1Te, and the concentration of impurities, Ag, Cu, Al, Fe, Na, Au and Ni decreased remarkably. The determination of two main processing parameters, the source end temperature and temperature gradient, had a strong effect on purification time, the furnace capacity and the physical and chemical properties of the impurities. In this experiment the relationship between the vapor pressure of Ag, Cu, Al, Fe, Na, Au and Ni and temperature were analyzed and the source end temperature was confirmed at 1173 K in the vacuum of 1.5 × 10− 2Pa. The mechanism of PVT was discussed and the process of PVT can be described by W. Palosz's thermochemical model [W. Palosz, S.L. Lehocaky, F. R. Szofran, Thermochemical model of physical vapor transport of cadmium-zinc telluride. Journal of Crystal Growth 148, 1995, 49–55]. The transport time dependence on gradient temperature was given. Considering purification time and the furnace capacity, temperature gradient of 13 K/cm were chosen.