Three-Dimensional Melt Flow Simulation for Nano Crystal-Originated Defects Formation in 300 mm Czochralski Processes

Unique crystal originated particle (COP) distribution, like a ring pattern, of grown in defects was seen on the 300 mm wafer surface with a laser scattering particle detection system. In our experiment analysis, the unique distribution of void defects was well matched with oxygen distribution. It shows that a strong relationship exist between void type defects and oxygen distribution. The oxygen distribution plays a key role in the distribution of void defects. Oxygen comes into the melt by dissolving silica crucible and then incorporates into the Silicon crystal. In our research, we interpreted the silicon melt convection in horizontal Magnetic Czochralski by using 3-dimensional unsteady numerical simulation and found abnormal melt convection under solid liquid interface that bring the unique distribution of oxygen concentration. Our simulation results were well explained the relationship between the melt flow and oxygen distribution. We sought a specific condition to resolve unique COP distribution problem by interpreting melt convection with variable magnetic conditions. Finally, our simulation approach was verified in experiment result.