Published online by Cambridge University Press: 26 February 2011
The Stillinger-Weber interatomic potential is used in molecular dynamics simulations to investigate the equilibrium, transport and aggregation properties of self-interstitials and vacancies in crystalline silicon at temperatures ranging from 500K to the melting point. The simulations predict equilibrium configurations of a < 110 > dumbbell for the single self-interstitial and an inwardly relaxed structure for the single vacancy. Both single-defect structures exhibit significant derealization at high temperatures resulting in strongly temperature dependent entropies of formation, as suggested by diffusion experiments. Diffusion coefficients and mechanisms for the single defects are predicted as a function of temperature. The results for the single point defects are discussed in the context of the existing literature values. Aggregation of two point defects is investigated by the computation of binding energies and entropies for these structures. Interstitials exhibit significant aggregation driving forces across the entire temperature range under simulation conditions, while vacancies aggregate less readily.