Study on Cd _0.9Mn _0.1Te growth behavior by Te solvent-Bridgman method

Cd _0.9Mn _0.1Te:In crystal ingot with size of φ30 mm×60 mm was grown through Te solvent-Bridgman method. IR transmittance and resistivity were measured to evaluate its crystalline quality. Chemical etching was applied to reveal the crystal defects, including dislocations, twins and Te inclusions. The macro- and micro-morphology of growth interface were quenched and observed with optical microscopy and infrared transmission microscopy. Te solvent-Bridgman method could effectively decline growth temperature and reduce the dislocation density in the ingot. The IR transmittance of wafers in the middle of the ingot reaches 60% and the bulk resistivity reaches 2.828×10 ¹¹ Ω·cm. The EPD of a good quality wafer is about 10 ⁶ cm ^-2, Te inclusions density measured through IR transmission microscopy is about 1.9×10 ⁴ cm ^-2 comparing with conventional Bridgman growth method. The quenched growth interface shows a slightly concaved appearance in macro-scale. However, the micro-scale interface is not smooth due to fast growth in quenching process. Meanwhile high density of Te inclusion near the interface was observed.