title: Carbon related defects in irradiated silicon revisited.
abstract: Electronic structure calculations employing hybrid functionals are used to gain insight into the interaction of carbon (C) atoms, oxygen (O) interstitials, and self-interstitials in silicon (Si). We calculate the formation energies of the C related defects Ci(SiI), CiOi, CiCs, and CiOi(SiI) with respect to the Fermi energy for all possible charge states. The Ci(SiI)(2+) state dominates in almost the whole Fermi energy range. The unpaired electron in the CiOi(+) state is mainly localized on the C interstitial so that spin polarization is able to lower the total energy. The three known atomic configurations of the CiCs pair are reproduced and it is demonstrated that hybrid functionals yield an improved energetic order for both the A and B-types as compared to previous theoretical studies. Different structures of the CiOi(SiI) cluster result for positive charge states in dramatically distinct electronic states around the Fermi energy and formation energies.
authors.affiliation: PSE Division, KAUST, Thuwal 23955-6900, Saudi Arabia.
authors.forename: H
authors.initials: H
authors.lastname: Wang
authors.affiliation: 1] Engineering and Innovation, The Open University, Milton Keynes MK7 6AA, United Kingdom [2] Department of Materials, Imperial College, London SW7 2AZ, United Kingdom.
authors.forename: A
authors.initials: A
authors.lastname: Chroneos
authors.affiliation: University of Athens, Solid State Physics Section, Panepistimiopolis Zografos, Athens 157 84, Greece.
authors.forename: C A
authors.initials: CA
authors.lastname: Londos
authors.affiliation: University of Athens, Solid State Physics Section, Panepistimiopolis Zografos, Athens 157 84, Greece.
authors.forename: E N
authors.initials: EN
authors.lastname: Sgourou
authors.affiliation: PSE Division, KAUST, Thuwal 23955-6900, Saudi Arabia.
authors.forename: U
authors.initials: U
authors.lastname: Schwingenschlögl
mesh_terms: D002244:Carbon / Q000737:chemistry*; D015394:Molecular Structure; D012825:Silicon / Q000737:chemistry* / Q000528:radiation effects*
chemical_list: D002244:Carbon; D012825:Silicon