Effects of cusp-shaped magnetic field on melt convection and oxygen transport in an industrial CZ-Si crystal growth

摘要

To clarify the effects of cusp-shaped magnetic field (CMF) on turbulent convection and oxygen transport in the melt, a set of 2D global simulations were conducted for growth of a 300 mm Czochralski-Si crystal. Turbulent melt convection was handled by a modified low-Re k-ε turbulence model with additional magnetohydrodynamic (MHD) terms. Three configurations of CMF were numerically compared. Different types of melt convection and growth interface geometry emerged as CMF configuration and magnetic field strength were varied. CMF configuration was found to be crucial in reducing oxygen dissolution from the crucible wall and oxygen incorporation into the crystal. The results demonstrated that the growth interface shape and the oxygen concentration at the growth interface can be controlled effectively by applying the appropriate CMF.