An investigation was made of the interaction of intrinsic point defects (vacancies and self-interstitials) with a partial dislocation in Si. By using a combination of zero-temperature ab initio total energy calculations with finite temperature free-energy calculations based on an interatomic potential, energies were obtained for the relevant core defects. The formation energies of vacancies and interstitials in the core of a 30° glide partial dislocation were considerably lower (by more than 1eV) than in the bulk. However, even at high temperatures, the predicted thermal concentration of shuffle segments, comprised of a row of vacancies or interstitials in the core, was low. Therefore, in the competition between 2 alternative positions (shuffle or glide {111} plane sub-sets) for the core of a 30° partial dislocation, the glide segment was strongly favored.

Point Defect Interaction with Dislocations in Silicon. J.F.Justo, M.de Koning, W.Cai, V.V.Bulatov: Materials Science and Engineering A, 2001, 309-310, 129-32