Photoluminescence study of beryllium implantation induced intrinsic defects in 6H-silicon carbide

Abstract

Beryllium was implanted into both n- and p-type 6H-SiC and the samples were subsequently annealed at 1600°C. Photoluminescence (PL) measurements were performed and PL lines at 420 and 472 nm were observed. The PL lines at around 420 nm have been detected from various ion implanted SiC samples and have been attributed to transitions involving some implantation induced intrinsic defect labeled as D II. The present observation of the PL lines at 420 nm from Be implanted 6H-SiC supports the intrinsic model that D II might be a carbon-di-interstitial defect. The lines at 472 nm labeled as D I in the PL spectra have previously been identified as divacancy defect (V Si−V C). We note that it was suggested that the electron traps labeled Z 1/Z 2 observed in deep level transient spectroscopy (DLTS) were due to the same divacancy defect. In our experiments, while the D I series PL lines are prominent, DLTS results from the same samples show no Z 1/Z 2 related peaks. The PL and DLTS results seem to be against the possibility that Z 1/Z 2 arise from the same defect.