Photoluminescence studies of annealing behaviour of the di-carbon radiation-damage centre in crystalline silicon

Abstract

Previously unreported photoluminescence lines are observed after the thermal destruction of the di-carbon centre (zero-phonon line at 969 meV or 7818 cm −1) in float zone and Czochralski silicon crystals. The point defects providing these photoluminescence lines involve carbon and oxygen atoms. The annealing of the di-carbon centres under heat treatment is not completely understood. The break-up process is not the only way to destroy the di-carbon centres and it is shown that the presence of other defects may affect the annealing process. We suggest that the di-carbon satellite sublines at 951.16 (7671), 952.98 (7686), 953.96 (7694) and 956.91 meV (7717 cm −1), are associated with the interstitial silicon atoms rather than vacancies.