Dislocation Locking by Intrinsic Point Defects in Silicon

ABSTRACTDislocation pileups with abnormally weak inter-dislocation repulsion have been observed in locally oxidized silicon structures. To verify if this could be attributed to elastic interaction of dislocations with intrinsic point defects, distributions of self-interstitials in dislocation stress fields have been studied using theoretical calculations and computer simulations. According to the obtained results, self-interstitials can form atmospheres about dislocations causing dislocation stress reduction and therefore screening of dislocations from interaction with external stresses. This may represent an additional mechanism of dislocation locking in silicon alternative to oxygen pinning.