Simulation of oxygen and carbon impurity transport during magnetically controlled Czochralski silicon growth

This study establishes a multi-field coupling model that includes a thermal field, flow field, oxygen and carbon impurity concentration field, and magnetic field, focusing on controlling the transport of oxygen impurities at the free surface of the melt. The effects of cusp magnetic field introduction, argon inlet flow velocity, and furnace pressure on the transport of oxygen and carbon impurities are analyzed, and the concentration field distribution of oxygen and carbon impurities within the furnace at the equal-diameter stage (300 mm) under different parameters is obtained. The results show that the method combining the cusp magnetic field with adjustments in furnace pressure and argon flow velocity can significantly reduce the oxygen concentration in the melt below the crystal and effectively expel oxygen and carbon impurities, providing optimization references for applying cusp magnetic fields and reducing oxygen and carbon impurities in the melt for large-sized Czochralski single-crystal silicon.