Arsenic diffusion was studied at 1000C in Si and relaxed Si0.9Ge0.1 structures grown using molecular beam epitaxy. Intrinsic diffusivity of As in Si0.9Ge0.1 was shown to be enhanced over Si by a factor of 2, in agreement with the literature. Using selective point defect injection, obtained by surface reactions achieved using rapid thermal annealing process under O atmosphere, clear evidence of the participation of both vacancy and interstitial defects in the diffusion process of As in Si as well as Si0.9Ge0.1 was obtained. Qualitatively, a higher contribution of vacancies in Si0.9Ge0.1 than in Si was apparent.

Evidence for a Vacancy and Interstitial Mediated Diffusion of As in Si and Si0.9Ge0.1. S.Uppal, A.F.W.Willoughby, J.M.Bonar, J.Zhang: Applied Physics Letters, 2004, 85[4], 552-4