Modified growth of Cd 1− xZn xTe single crystals

Abstract

Good quality Cd 1− x Zn x Te ( x=0.04) single crystals 20 mm in diameter and 45 mm in length were grown by a modified growth technique, i.e. descending ampoule with rotation. Synthesis of the polycrystalline material using the melt temperature oscillation method (MTOM) and growth of Cd 0.96Zn 0.04Te single crystals were carried out in the same quartz ampoule without transfer between the steps. The as-grown crystal was characterized by using X-ray diffraction, IR transmission microscopy, FTIR spectroscopy and scanning electron microscopy (SEM). It was found that there is a (1 1 0) cleavage face in the as-grown crystal, multiple diffraction peaks of the {1 1 0} faces were evident, the transmission of the crystal sample of 30 mm thickness is up to 62% in the range from 6500 to 400 cm −1, the absorption coefficient is 0.021 cm −1. The surface of the {1 1 0} oriented wafer showed perfect homogeneous growth steps. The results showed that not only is MTOM a new effective method for synthesizing high-purity single-phase Cd 1− x Zn x Te polycrystalline materials, but also that the modified growth technique (descending ampoule with rotation) is a new promising method for growing high-quality Cd 1− x Zn x Te single crystals. Further, the crystal grown, using the polycrystalline materials synthesized by the modified growth technique shows neither any sign of phase separation nor ordering effects or structure distortion. The quality of the crystal is good.