Effective Diffusion Coefficient and Controlling Process of P Diffusion in Si Based on the Pair Diffusion Models of Vacancy and Interstitial Mechanisms

Based on the pair diffusion models of vacancy and interstitial (V and I) mechanisms, the V and I components of effective P diffusion coefficient, DP+,Veff and DP+,Ieff, and the controlling process of P diffusion in Si are obtained. Assuming that the I mechanism is dominant, not only the I- concentration, CI- , but also its gradient, d CI- /d λ, is effective on DP+,Ieff at high CP+ . DP+,Ieff is large at d CI- /d λ 0. P+ and I- are generated by the dissociation of P–I pair. When excess I- thus generated is removed, d CI- /d λ 1×1020 cm-3 (s: surface).