Simulation of oxygen precipitation in CZSi crystal during the pulling process

We present a simulation model for the defect formation process in the silicon crystal. It is assumed that the grown-in defects in the CZSi crystal are oxygen precipitates which grew on the clusters of excess vacancy as nucleation sites. The nucleation rate of vacancy aggregates is calculated by classical theory. The oxygen precipitation and growth of precipitates are estimated by the simulation model of Schrems. The simulation results correspond well with the defect density in 150 mm diameter CZ crystals grown under various thermal gradient conditions, as observed by laser scattering tomography.