A Three Dimensional Numerical Simulation for the Transport Structures in Liquid Phase Electroepitaxy Under Applied Magnetic Field
Y.C. Liu, S. Dost and H. Sheibani
The article presents a three-dimensional numerical simulation for the transport structures, namely fluid flow, and heat and mass transport in the liquid solution in Liquid Phase Electroepitaxial (LPEE) crystal growth of GaAs under the effect an applied magnetic field. LPEE growth experiments at higher magnetic field levels were not satisfactory, led to uneven growth and holes in the grown crystals. It is possible that such growth is due to the strong convection in the solution zone. In order to shed light on the experimental observations, the LPEE growth process was simulated numerically. Since the growth rate was the same for both the binary (GaAs) and ternary (In<sub>0.04</sub>Ga<sub>0.96</sub>As) systems in our experiments, a binary system was considered in the simulation for simplicity. Various magnetic field and electric current density levels were considered. In spite of the assumed axisymmetric boundary conditions, the computed flow field in the solution exhibited interesting three dimensional structures. The flow was suppressed up to a critical magnetic field level (about 2.0 kG), and became very strong at higher magnetic field levels. At higher magnetic field levels, the flow patterns show very strong localized structures near the growth interface, which may explain the uneven growth and holes observed in the grown crystals.