A three-dimensional computational analysis of the influence of magnetic field on the growth of CdTe single crystals by the traveling heater method

A three-dimensional numerical simulation for the THM (Travelling Heater Method) growth of CdTe single crystals under an applied (vertical) static magnetic field was carried out. The effect of magnetic field intensity on the transport structures (fluid flow, concentration and temperature fields) in the liquid solution was investigated. Numerical results show that the transport structures in the liquid solution exhibit three, distinct behavior at different field intensity levels. There is a critical magnetic field level, about 8.0 kGauss, below which the applied magnetic field is very beneficial; suppresses the convection and leads to more uniform concentration and temperature distributions and flatter growth interfaces for a prolonged and stable growth. It appears that the field intensity of 8.0 kGauss is the optimum level for which the convection was suppressed to a minimum and the growth interface was the flattest. At field higher levels, the flow structures first show a transitional behaviour and then become very strong and unstable. The computed flow and temperature fields indicate that higher magnetic field levels may in deed lead to unstable transport structures in growth experiments. (author)