Impact of oxygen on the diffusion of silicon in germanium: density functional theory calculations

In the present study, density functional theory calculations have been used to predict the binding energies of clusters formed between lattice vacancies, silicon and oxygen atoms (SixOyVz) and the energy barriers associated with the migration of silicon in germanium in the presence of oxygen. It is predicted that SixOyVz clusters are stable. The results are discussed in view of recent experimental studies (Silvestri et al Semicond. Sci. Technol. 21, 758 (2006)), which suggest that the association of oxygen with silicon and vacancies leads to a retardation of silicon diffusion in germanium