Vacancy-Fluorine Clusters in Silicon

Abstract

Fluorine (F) doping and the formation of F-vacancy (FnVm) clusters have been extensively studied in silicon (Si) as they can suppress the transient self-interstitial mediated diffusion of boron (B). Recent experimental studies by Bernardi et al. revealed that there is no significant concentration of FnVm clusters (for n ≥ 4, m ≥ 1) in disagreement with a number of density functional theory studies. In the present study we use electronic structure calculations to evaluate the binding energies of FnVm clusters and Vn clusters. The significant binding energies of the Vn clusters reveals that the concentration of the large FnVm clusters (n ≥ 4, m ≥ 1) will be limited compared to the Vn clusters or even smaller clusters.