Self-diffusion measurements were extended to temperatures of 800 to 900C by monitoring 30Si diffusion in isotopically enriched structures. By comparing P, Sb and Si diffusion (table 8, figure 7) under non-equilibrium conditions, it was deduced that the interstitial-mediated fraction of self-diffusion lay between 0.50 and 0.62 at temperatures ranging from 800 to 1100C. This permitted activation enthalpies of 4.68 and 4.86eV to be determined for the interstitial and vacancy mechanisms, respectively. These results differed from those found for metal diffusion experiments.

Self-Diffusion in Silicon - Similarity between the Properties of Native Point Defects A.Ural, P.B.Griffin, J.D.Plummer: Physical Review Letters, 1999, 83[17], 3454-7

Table 8

Diffusivity Ratios of 30Si, P and Sb in Si during Oxidation at 800 to 1100C

Figure 7

Diffusion of P, Sb and Si in Si