Stable fourfold configurations for small vacancy clusters in silicon from ab initio calculations.

Phys Rev Lett

Département de Physique et Regroupement Québécois sur les Matériaux de Pointe, Université de Montréal, Case Postale 6128, Succursale Centre-Ville, Montréal, Québec H3C 3J7, Canada.

Published: June 2004

Using density-functional-theory calculations, we have identified new stable configurations for tri-, tetra-, and pentavacancies in silicon. These new configurations consist of combinations of a ring hexavacancy with three, two, or one interstitial atoms, respectively, such that all atoms remain fourfold. As a result, their formation energies are lower by 0.6, 1.0, and 0.6 eV, respectively, than the "part of a hexagonal ring" configurations, believed until now to be the lowest-energy states.

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http://dx.doi.org/10.1103/PhysRevLett.92.255504DOI Listing

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