Atomistic Model of Transient Enhanced Diffusion and Clustering of Boron In Silicon

Abstract

ABSTRACTAn atomistic model for B implantation, diffusion and clustering is presented. The model embodies the usual mechanism of Si self-interstitial diffusion and B kick-out and also includes the formation of immobile precursors of B clusters prior to the onset of transient enhanced diffusion. These immobile complexes, such as BI2 (a B atom with two Si self-interstitials) form during implantation or in the very early stages of annealing, when the Si interstitial concentration is very high. They then act as nucleation centers for the formation of B-rich clusters during annealing. This model explains and predicts the behavior of B under a wide variety of implantation and annealing conditions.