ARE SELF-INTERSTITIALS REQUIRED TO EXPLAIN NONEQUILIBRIUM DIFFUSION PHENOMENON IN SILICON?
The possibility that vacancies are the only type of intrinsic point defects present in silicon is investigated using enhanced and retarded diffusion phenomena of substitutional dopants, such as oxidation-enhanced diffusion (OED) and oxidation-retarded diffusion (ORD). It is shown that an undersaturation of vacancies leads to enhanced dopant diffusion, if this diffusion occurs predominantly via an interstitial-substitutional diffusion mechanism (Frank-Turnbull mechanism). This model is in accord with the observed doping dependence of dopant diffusion. However, a quantitative treatment of the growth of oxidation-induced stacking faults shows that the presence of self-interstitials is required to explain the experimental data.