Deciphering mechanisms of enhanced-retarded oxygen diffusion in doped Si

Abstract

In this letter, we study enhanced-retarded diffusion of oxygen in doped silicon by means of first principle calculations. We found that the migration of oxygen dimers can not be significantly affected by strain, doping type or rate. We attribute the enhanced oxygen diffusion in p-doped silicon to reduced monomer migration energy, and the retarded oxygen diffusion in Sb-doped to oxygen trapping close to a dopant site. The two proposed kinetic and thermodynamic mechanisms can appear at the same time and might lead to contradictory experimental results. Such mechanisms can be involved in the light induced degradation phenomenon in solar grade silicon.