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

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.

arXiv commentRevTeX 4, 6 pages, 3 figures Changes in version 2: Section headings, footnote included in text, vibrational data now given for neutral split-interstitial, extended discussion of the [(C_2)_Si]_2 defect incl. figure Changes version 3: Correction of binding energy for 3rd and 4th carbon atom at antisite; correction of typos

References in corpus (3)

• Ab initio pseudopotentials for electronic structure calculations of poly-atomic systems using density-functional theory
• Density-functional theory calculations for poly-atomic systems: Electronic structure, static and elastic properties and ab initio molecular dynamics
• Ab initio study of the migration of intrinsic defects in 3C-SiC

Cited by in corpus (2)

• Structure and vibrational spectra of carbon clusters in SiC
• Thermally stable carbon-related centers in 6H-SiC: photoluminescence spectra and microscopic models