Growth of Different Crystals Using a Modified Bridgman System

This paper studies the favorable growth conditions for the III-V and II-VI crystals such as InAs, InSb, GaSe, GaP, PbTe and CdTe by the Bridgman technique. Numerical simulations have been conducted to investigate the flow field, temperature distribution in relation to the solidification interface shape and growth conditions for various materials. It is concluded that the growth is strongly affected by melt convection; a strong convection may destroy the interface stability, resulting in failed growth. The Grashof and Prandtl numbers are identified as the key parameters affecting the growth interface stability. Based on these two parameters, a growth process map is developed to quantify the difficulty of growth for different materials by Bridgman technique. To accommodate the growth of large diameter crystal, a new growth system based on Bridgman configuration is proposed in which two hot-zone furnace is introduced and the feasibility of using this system to suppress the melt convection, subsequently generating favorable growth conditions has been confirmed from the numerical simulations.