Intrinsic point defects in crystalline silicon: Tight-binding molecular dynamics studiesof self-diffusion, interstitial-vacancy recombination, and formation volumes

Abstract

Tight-binding molecular dynamics simulations are performed to study self-diffusion, interstitial-vacancy recombination, and formation volumes of point defects in crystalline silicon. The results show that (i) self-diffusion is dominated by vacancies (V) at low temperature and by interstitials (I) at high temperature; (ii) interstitial-vacancy recombination at room temperature leads to formation of a metastable I-V complex, which has an annihilation energy barrier of 1.1 eV; (iii) interstitial and vacancy relaxation volumes in silicon are approximately equal in magnitude and opposite in sign.