By using molecular dynamics simulation techniques, an investigation was made of the effect that point defects and interstitial-vacancy complexes had upon the Si amorphization process. It was observed that the accumulation of interstitial-vacancy complexes at concentrations of 25% and above led to homogeneous amorphization. However, the basic properties of the interstitial-vacancy complex were determined, and this showed that it was not as stable at room temperature as had previously been reported. From the present simulations, more stable defect structures were identified which consisted of a combination of complexes and Si self-interstitials. These defects form when there was an excess of interstitials or by incomplete interstitial-vacancy recombination in a highly damaged lattice. Unlike the interstitial-vacancy complex, 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.

Stability of Defects in Crystalline Silicon and their Role in Amorphization. L.A.Marqués, L.Pelaz, J.Hernández, J.Barbolla, G.H.Gilmer: Physical Review B, 2001, 64[4], 045214 (9pp)