Suppression of melt convection in a proposed Bridgman crystal growth system

Abstract

Numerical simulations are performed for Bridgman crystal growth of several semiconductor materials, such as InAs, InSb, GaSe, CdTe, PbTe, and GaP. For materials with low Prandtl and low Grashof numbers, melt convection is weak and the traditional Bridgman technique is a suitable growth process. For the materials with high Prandtl numbers in their melt status and the growth system with high Grashof number, the temperature field and the growth interface are significantly influenced by melt flow, resulting in the complicated flow pattern and curved interface shape. A new Bridgman crystal growth system is proposed to suppress convection and improve solidification interface shape by cooling of the top melt. The results obtained from the proposed design demonstrate that melt convection may be controlled by adjusting the design parameters. Further, parametric studies are performed to determine the influence of the control parameters on melt flow and solidification interface.