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

D. V. Makhov·Laurent J. Lewis
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Abstract

Using density-functional-theory calculations, we have identified new stable configurations for tri-, tetra-, and penta-vacancies 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 up to now to be the lowest-energy states.

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D. V. Makhov, Laurent J. Lewis. 2004-05-07. Stable fourfold configurations for small vacancy clusters in silicon from ab initio calculations. https://doi.org/10.1103/physrevlett.92.255504

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