The Role of Incomplete Interstitial-Vacancy Recombination on Silicon Amorphization

We investigate the role that point defects and interstitial-vacancy pairs have on the Si amorphization process using molecular dynamics techniques. We show that accumulation of interstitial-vacancy pairs in concentrations of 25% and above lead to homogeneous amorphization. We identify very stable defect structures, consisting of the combination of the pair and Si self-interstitials, which form when there is an excess of interstitials or by incomplete interstitial-vacancy recombination in a highly damaged lattice. These defects could survive long enough at room temperature to act as embryos for the formation of extended amorphous zones and/or point defect clusters.