Numerical simulation of oscillatory flow in melt during InSb single crystal growth by RF heating Czochralski method

Oscillatory flow present in the melt during InSb single crystal growth usin g an RF-heating Czochralski method has been numerically investigated by mea ns of the finite difference method using the HSMAC algorithm. The thermal b oundary conditions required for the numerical simulation model were obtaine d experimentally by measuring the temperature profile along the crucible of a Czochralski system by means of thermocouples mounted in the crucible. Re sults of numerical simulations showed that the use of a third-order upwind discretization scheme was necessary to catch the oscillatory behaviour of t he fluid flow in the melt. It was shown that this oscillatory behaviour str ongly depends on the crystal rotation rate. Indeed, the oscillation period increases when the crystal rotation rate is above a critical rotation rate. In order to avoid such oscillations, crystal rotation rates lower than thi s critical value of crystal rotation rate must be selected for the growth o f high quality crystals free of striations. (C) 1998 John Wiley & Sons, Ltd .