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Ab initio study of the migration of intrinsic defects in 3C-SiC

Michel Bockstedte·Alexander Mattausch·Oleg Pankratov
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Abstract

The diffusion of intrinsic defects in 3C-SiC is studied using an ab initio method based on density functional theory. The vacancies are shown to migrate on their own sublattice. The carbon split-interstitials and the two relevant silicon interstitials, namely the tetrahedrally carbon-coordinated interstitial and the <110>-oriented split-interstitial, are found to be by far more mobile than the vacancies. The metastability of the silicon vacancy, which transforms into a vacancy-antisite complex in p-type and compensated material, kinetically suppresses its contribution to diffusion processes. The role of interstitials and vacancies in the self-diffusion is analyzed. Consequences for the dopant diffusion are qualitatively discussed. Our analysis emphasizes the relevance of mechanisms based on silicon and carbon interstitials.

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Michel Bockstedte, Alexander Mattausch, Oleg Pankratov. 2003-09-30. Ab initio study of the migration of intrinsic defects in 3C-SiC. https://doi.org/10.1103/physrevb.68.205201

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