Numerical simulation of THM growth of CdTe in presence of rotating magnetic fields (RMF)

The influence of rotating magnetic fields (RMF) on flow pattern and compositional uniformity in the solution zone of a traveling heater method (THM) system for growth of CdTe is numerically investigated. The analysis is conducted at the 10-6 and 10-1g0 as representative of space and ground processing conditions. It is shown that under microgravity conditions application of RMF can be used to overwhelm residual buoyancy-induced convection and to control the uniformity of solution-zone composition at the growth front without appreciable modification of the growth interface shape. At high-gravity levels, RMF is found not to be able to completely dominate buoyancy-induced convection. In this regime, for the range of field strengths studied, RMF is found to result in (a) complex flow structures in the solution zone, (b) enhancement of compositional nonuniformities at the growth front, and (c) increased convexity of the growth interface. A scaling analysis of convection in the solution zone is used to generate a nondimensional map delineating the RMF- and gravity-dominated flow regimes.