Divacancy model for P6/P7 centers in 4H- and 6H-SiC

摘要

Electron paramagnetic resonance (EPR) studies of the P6/P7 centers in 4H- and 6H-SiC are reported. The obtained principal values of the hyperfine tensors of C and Si neighbors are in good agreement with the values of the neutral divacancy (V_CV_(Si)~0) calculated by ab initio supercell calculations. The 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 (V_CC_(Si)~(2+)), are related to the triplet ground states of the C_(3v)/C_(1h) configurations of V_CV_(Si)~0.