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Carbon antisite clusters in SiC: a possible pathway to the D_{II} center

Alexander Mattausch·Michel Bockstedte·Oleg Pankratov
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Abstract

The photoluminescence center D_{II} is a persistent intrinsic defect which is common in all SiC polytypes. Its fingerprints are the characteristic phonon replicas in luminescence spectra. We perform ab-initio calculations of vibrational spectra for various defect complexes and find that carbon antisite clusters exhibit vibrational modes in the frequency range of the D_{II} spectrum. The clusters possess very high binding energies which guarantee their thermal stability--a known feature of the D_{II} center. The di-carbon antisite (C_{2})_{Si} (two carbon atoms sharing a silicon site) is an important building block of these clusters.

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Alexander Mattausch, Michel Bockstedte, Oleg Pankratov. 2004-02-04. Carbon antisite clusters in SiC: a possible pathway to the D_{II} center. https://doi.org/10.1103/physrevb.69.045322

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