Effect of the crystal–melt interface on the grown-in defects in silicon CZ growth

Single crystals of 206 mm diameter are grown by magnetic Czochralski method in different growing conditions. Effect of the shape of the crystal–melt interface on the defect behavior in the crystal is experimentally investigated. In order to obtain the various shapes of the interfaces, the melt convection is changed with various heating conditions, which are different crucible positions at a fixed heater, and various heaters. The crystal–melt interface becomes more concave (convex to the crystal) with increasing natural convection and the critical pulling speed for defect-free crystal increases. The experimental results are numerically analyzed.