First-Principles Study of Boron Diffusion in Silicon
نویسندگان
چکیده
In this Letter we investigate boron diffusion as a function of the Fermi-level position in crystalline silicon using ab initio calculations. Based on our results, a new mechanism for B diffusion mediated by Si self-interstitials is proposed. Rather than kick out of B into a mobile channel, we find a direct diffusion mechanism for the boron-interstitial pair for all Fermi-level positions. Our activation energy of 3.5 3.8 eV, migration barrier of 0.4 0.7 eV, and diffusion-length exponent of 20.6 to 20.2 eV are in excellent agreement with experiment.
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