Electron paramagnetic resonance spectra were observed, at above 25K, in p-type 4H and 6H samples which had been irradiated with electrons. The center had C3v symmetry, with an electron spin of S = 1/2. By using high-frequency (95GHz) electron paramagnetic resonance, it was possible to obtain the detailed hyperfine structure which was due to interaction with the 4 nearest Si neighbours and to identify the defect as being a C vacancy in the positive charge-state. The g-values and hyperfine tensors of the center were almost the same in both polytypes, and no dependence upon the inequivalent lattice sites was detected.

Carbon Vacancy-Related Defect in 4H and 6H SiC. N.T.Son, P.N.Hai, E.Janzén: Physical Review B, 2001, 63[20], 201201 (4pp)