The contributions of neutral and charged silicon self-interstitials to self- and boron- diffusion during transient enhanced diffusion in silicon were investigated. Self- and boron- diffusion were simultaneously observed by using natSi/28Si isotope superlattices. Calculations based upon diffusion equations involving {311} defects and boron-interstitial cluster models were used to reproduce diffusion profiles in silicon-implanted (intrinsic) and boron-implanted (extrinsic) silicon isotope superlattices, followed by annealing. To investigate the diffusion processes, the time evolution of the silicon self-interstitial profiles during transient diffusion was simulated. The results demonstrated directly that excess neutral self-interstitials predominantly enhanced self-diffusion during the transient process under intrinsic conditions, while doubly positively charged self-interstitials dominated self-diffusion under extrinsic conditions.

Behaviors of Neutral and Charged Silicon Self-Interstitials during Transient Enhanced Diffusion in Silicon Investigated by Isotope Superlattices. Y.Shimizu, M.Uematsu, K.M.Itoh, A.Takano, K.Sawano, Y.Shiraki: Journal of Applied Physics, 2009, 105[1], 013504