It was shown that B and P exhibited suppressed and As and Sb enhanced diffusion in Si with C atom concentrations of about 1020/cm3. Since B and P diffuse via an interstitial mechanism and Sb and As diffuse via a vacancy mechanism, this indicated a suppressed density of self-interstitials and an enhanced density of vacancies in C-doped Si. Simultaneous measurements of vacancy supersaturation by means of Sb diffusion and of the clustering kinetics of C were used to study the annihilation of excess vacancies at the Si surface. The surface acts as an effective sink for vacancies with a recombination length of up to 70nm.

Non-Equilibrium Point Defects and Dopant Diffusion in Carbon-Rich Silicon. H.Rücker, B.Heinemann, R.Kurps: Physical Review B, 2001, 64[7], 073202 (4pp)