Control of Oxygen Transport in the Melt of a Czochralski-Silicon Crystal Growth

The concentration and distribution of oxygen incorporated into a grown crystal have significant effects on the silicon crystal quality. We investigated the influences of different parameters on the oxygen transport in the melt in a Czochralski-silicon (CZ-Si) crystal growth. First, the effects of transverse magnetic fields on the melt convection and oxygen transport were investigated. It was found that the oxygen transported from the crucible walls to the melt−crystal interface is effectively reduced with transverse magnetic fields. Then, the effects of crucible and crystal rotation rates on the oxygen transport were investigated under transverse magnetic field conditions. The results showed that increases in the crystal and crucible rotation rates both change the bulk flow structures and lead to an increase in the oxygen concentration at the melt−crystal interface. The influences of crucible rotation rate are more intensive than that of the crystal rotation rate.