Abstract
The development of Czhochralski silicon crystal 400 mm in diameter is progressing in Japan. The influence of a cusp magnetic field on thermal environment of huge silica crucible has been investigated by computer simulation. We expect that suppression of melt convection by Lorentz force can elongate the life time of silica crucible. Magnetic field slows down the melt flow and hence reduce the oxygen transport and the dissolution speed. We found the optimum magnetic strength with 36 and 48 inch silica crucible was about 2000 0e. In this region, crucible temperature was lower than in the absence of a magnetic field and temperature fluctuation in the molten silicon was very small. On the other hand, the oscillation of melt temperature was observed with the magnetic strength of 300 0e. the 2000 Oe, magnetic field leads to a rise in teh crucible wall temperature and softenit.
