Numerical study of continuous Czochralski (CCz) silicon single crystal growth in a double-side heater

Abstract

The effect of heater power control on heat, flow, and oxygen transport for the CCz growth of 8-inch diameter silicon crystal in a triple-crucible was numerically studied. Three different designs of a double-side heater at different power ratios of the lower and upper side heaters (PRSD = 0.25, 1, and 4) were compared with the case of a single-side heater. For the cases considered in the present work, a design in which the upper side heater was shorter than the lower one at PRSD = 0.25 could be a good choice for improving the crystal quality and CCz growth. This was shown by the reductions in the crystal-melt interface deflection and oxygen content and the increase in the melt temperature in the feeding zone. In this case, reducing the interface deflection and crucible bottom wall temperature could enhance the pulling speed. However, the power consumption in this condition was higher than that in the single-side heater case. Achieving a lower heater power was feasible with a higher PRSD value. However, it was important to note that the oxygen content would be higher, and the melt temperature in the outer melt significantly dropped.