Modeling of high pressure, liquid-encapsulated Czochralski growth of InP crystals

Abstract

A high resolution numerical scheme based on multizone adaptive grid generation and curvilinear finite volume discretization has been implemented to simulate the high pressure, liquid-encapsulated Czochralski (HPLEC) growth of InP crystals and study the effect of gas recirculation on melt flow and crystal/melt interface shape. The model incorporates flows induced by buoyancy and capillary forces and by crystal and crucible rotations, as well as the radiation heat loss from the melt and the crystal surfaces. It is demonstrated that the thermal interaction between the gas and the melt must be accounted for to predict the interface shape and dynamics accurately. The numerical results demonstrate that the transport phenomena in a high pressure growth system is very complex. The temperature distribution in the crystal and the shape of the melt/crystal interface also change significantly with the size of the crystal. This has a strong influence on dislocations in the crystal as shown by the experiments of Kohiro et al. [J. Crystal Growth 158 (1996) 197] and Jordan et al. [J. Crystal Growth 70 (1984) 555].