Boron diffusion in silicon in inert and oxidizing ambient and extrinsic conditions

Abstract

Recent experimental data of the diffusion coefficient of boron in inert and oxidizing ambient as a function of substrate concentration are interpreted assuming a dual vacancy and interstitialcy mechanism. Supposing also that positively ionized vacancies and interstitials dominate the contribution of the corresponding neutral species a simple model is developed that explains well the experiments when boron diffuses alone and when it diffuses in heavily phosphorus‐doped silicon. It is concluded that the interstitialcy component is limited between 0.21 < fI < 0.43 showing an important vacancy contribution to the diffusion of boron.

Determination of aluminum diffusion parameters in silicon

“…Because of high dopant concentrations, the suppression of oxidation enhancement was presumed. 27 As- suming also total electrical activation of boron in Fig. 5, the diffusivity enhancement D ex Al /D i Al of aluminum is plotted versus the normalized hole concentration.…”