Correlation between the x value and qualities of Cd_1-xZn _xTe crystal grown by vertical Bridgman method

Three Cd_1-xZn_xTe ingots with x values of 0.10, 0.15, and 0.20 were respectively grown by vertical Bridgman method (VBM). Techniques including addition of excess Cd into the stoichiometric starting raw materials and accelerated crucible rotation were applied during the crystal growth process. The as-grown ingots were then characterized by concentration distribution, dislocation, Te precipitate/inclusion, IR transmission, resistivity, and impurity concentration, respectively. It was found that with the increase of the x value, all the qualities but resistivity became worse. As for the resistivity, Cd_0.85Zn_0.15Te possessed the highest one which was about one order higher than both Cd_0.9Zn _0.1Te and Cd_0.8Zn_0.2Te. Analyses indicated that the growth temperature rise of Cd_1-xZn_xTe with the x value led to more defects and impurities and thus degraded the crystal qualities, while the resistivity rise of Cd_1-xZn_xTe with the x value and the availability of the applied new techniques made Cd _0.85Zn_0.15Te obtaining the highest resistivity.