Simulation analysis for the ring patterned void defect in silicon mono crystal

The ring patterned void distribution has been investigated by using numerical simulation. First, the mechanism of oxygen incorporation during Cz process was studied by calculating 3D melt flow. The silicon melt flow greatly affected the oxygen incorporation. In particular, the magnetic field plays a key role to control silicon melt flow in a large diameter crystal growth. In our experimental results, the ring patterned void distribution was usually found not under the cusp magnetic field condition but under the horizontal magnetic field. We compared the melt flow under two magnetic field conditions and explained the mechanism of oxygen incorporation. Second, the formation of void type defects was investigated using the KLMC method, which is an effective method of estimating unique void-type defects in silicon crystal. The vacancy-oxygen reaction was analyzed to describe the formation of striation patterned void defects. The vacancies were easily trapped by the oxygen and thus the number of clusters increased with the oxygen concentration. The density of the clusters as a function of the oxygen concentration agreed well with the experiment observations. When the system had locally limited high oxygen concentration area, the number of clusters dramatically increased in that area. Such changes in the clusters can significantly affect the dynamics of void formation. The striation patterned COP phenomenon in the experiment was well explained, and these KLMC simulations can help to improve the representation of such effects in macro-scale process models.