Numerical simulation of the horizontal Bridgman growth of a gallium arsenide crystal

Two-dimensional numerical simulations have been developed which represent the thermomechanical behavior of semiconductor melts in horizontal crucibles. These computer models are based on time-dependent finite-difference and finite-element codes, capable of simulating steady and transient melt convection. At moderate Rayleigh numbers, one finds time-invariant solutions which typically involve several primary and secondary vortices, depending on aspect ratio. Above a critical Rayleigh number, these steady solutions are replaced by oscillatory melt convection, as suggested by earlier experimental and analytic studies. The finite element code was extended to include a solid-liquid interface, which permits the study of actual crystal growth processes.