ATOMISTIC SIMULATION OF POINT-DEFECTS IN SILICON AT HIGH-TEMPERATURE

The Stillinger-Weber interatomic potential is used in molecular dynami cs simulations to compute estimates of the equilibrium and transport p roperties of self-interstitials and vacancies in crystalline silicon a t high temperature. Equilibrium configurations are predicted as a (110 ) dumbbell for a self-interstitial, and as an inwardly relaxed configu ration for a vacancy. Both structures show considerable delocalization with increasing temperature, which leads to a strong temperature depe ndence of the entropy of formation, as suggested by diffusion experime nts. Diffusion coefficients and mechanisms are predicted as a function of temperature. The predictions are discussed in the context of exper iments and first-principle calculations. (C) 1996 American Institute o f Physics.