A detailed study was made of the energetics of As-vacancy reactions, and of the lattice distortions surrounding the As-vacancy defect, by using an ab initio plane-wave pseudopotential method and the density functional theory. A potential-energy diagram of As-vacancy separations was presented which could be used in atomistic diffusion simulations. Calculations were also made of the binding energy and of the formation energy of vacancy complexes such as AsV, As2V and AsV2. It was found that the stable configuration of As2V was As-V-As, whereas the stable configuration of AsV2 was As-V-V. The nature of the binding between As and vacancies was explained in terms of lattice distortions and changes in chemical bond configuration which were introduced by the As-vacancy complex.

Ab initio Calculations of the Structure and Energetics of As-Vacancy Complexes in Silicon J.Xie, S.P.Chen: Journal of Physics D, 1999, 32[11], 1252-7