Identification of divacancies in 4H-SiC

The P6/P7 centers in 4H-SiC were studied by electron paramagnetic resonance (EPR) and ab initio supercell calculations. The hyperfine coupling constants of C and Si neighbors obtained by EPR are in good agreement with the calculated values for the neutral divacancy, VCVSi0. Our results suggest that the P6/P7 centers, which were previously assigned to the photo-excited triplet states of the carbon vacancy–carbon antisite pairs in the double positive charge state (VCCSi2+), are related to the triplet ground states of the C3v/C1hC3v/C1h configurations of VCVSi0.