Calculation of thermodynamic and transport properties of intrinsic point defects in silicon.

Abstract

A systematic analysis is presented for the calculation of thermodynamic and transport properties of intrinsic point defects in silicon based on atomistic simulations using the Stillinger-Weber interatomic potential [F. H. Stillinger and T. A. Weber, Phys. Rev. B 31, 5262 (1985)]. Results are computed from a robust combination of lattice statics and Monte Carlo simulations, the quasiharmonic approximation for calculation of reference-state free energies, and the cumulant analysis of the enthalpy distribution function. Results are presented for formation properties and thermal equilibrium concentrations of vacancies and self-interstitials and for transport properties of vacancies in silicon. The calculated formation properties and thermal equilibrium concentrations of both intrinsic point defects and the migration enthalpy of the vacancy are in reasonable quantitative agreement with experimental data and analyses of dopant diffusion data. The calculations support the extended interstitial model and provide an internally consistent data base for constitutive and numerical modeling of substitutional species transport in silicon.