Stability of planar crystal-melt interface during vertical Bridgman growth of gallium antimonide

Abstract

The stability of planar crystal-melt mtel ace shape during the growth of gallium antimonide (GaSh) by vertical Bridgman technique under different experimental conditions has been evaluated. To achieve planar melt-solid interface. a critical ratio of temperature gradient of the furnace at the melting point (G) to ampoule lowering rate (V) was found necessary. The value of G/V was found to deviate as a result of perturbation in various experimental parameters such as the melt thermal conductivity, the ampoule geometry. the mode of heM extraction from the tip of the ampoule and the extent of lateral heat loss from the side walls of the ampoule. Nevertheless. the ON values were found to lie in a narrow range in our experiments. Expectedly, crystals grown by employing the flat melt-solid interface exhibited superior quality than those with nonplanar ones.