Numerical Simulation of the Effect of Heater Position on the Oxygen Concentration in the CZ Silicon Crystal Growth Process

Abstract

We perform numerical simulations to analyze the effect of the position of the heater on the thermal and flow fields and the oxygen concentration distribution during the industrial Cz silicon crystal growth process. The amount of oxygen released from the silica crucible to the silicon melt during the growth process can be lowered by adjusting the heater position to decrease the temperature on the crucible wall. During growth of the crystal body, there is a significant decrease in the gradient of the oxygen concentration along the melt-crystal interface due to the stronger Taylor-Proudman vortex, which is generated by the crucible and crystal rotation. There is a significant reduction in the average oxygen concentration at the melt-crystal interface for longer crystal lengths because of the lower wall temperature, smaller contact surface between the crucible wall and the melt and the stronger Taylor-Proudman vortex.