Process for suppressing the nucleation and/or growth of interstitial type defects by controlling the cooling rate through nucleation

Abstract

The present invention relates to a process for growing a single crystal silicon ingot, which contains an axially symmetric region having a predominant intrinsic point defect and which is substantially free of agglomerated intrinsic point defects in that region. The process comprising cooling the ingot from the temperature of solidification to a temperature of less than 800° C. and, as part of said cooling step, quench cooling a region of the constant diameter portion of the ingot having a predominant intrinsic point defect through the temperature of nucleation for the agglomerated intrinsic point defects for the intrinsic point defects which predominate in the region.