Application of Rotating Magnetic Fields to THM Growth Process: Te-CdTe

The numerical simulation of ongoing traveling heater method (THM) solution growth experiments of CdTe from Te solvent and the influence of a Rotating Magnetic Field (RMF) on control of convection in the solution zone is presented. The application of RMF is pursued as a means to actively control thermo-solutal convection in the solution zone which otherwise would be dominated by buoyancy forces. Numerical simulation and scaling analysis are used to generate a flow-regime map demarcating the boundary separating the buoyancy- and RMF-driven convection in the solution zone. Results indicate that whereas at low gravity levels the application of RMF can completely overwhelm buoyancy-induced convection, at normal gravity levels the successful control of convection by RMF requires use of fairly thin solvent zones. Simulation results also indicate that field strengths required to dominate natural convection on earth may lead to instabilities and transition to turbulence, and an associated deleterious effect on the quality of grown crystals. These and other simulations results are discussed in reference to experimental evidence.