Electron paramagnetic resonance methods were used to study defects in p-doped type-4H and 6H material which had been irradiated with 2.5MeV electrons at 400C. Following irradiation, an anisotropic electron paramagnetic resonance spectrum with monoclinic symmetry (C1h) and an effective spin of S = 1 was observed in both polytypes. The same g-tensor was found for the spectra from both polytypes. The z- and x-axes lay in the (11▪0) plane, and the y-axis which was perpendicular to this plane. The angle between the z-axis and the c-axis was 54º. The fine structure parameters were equal to 0.0328 and 0.0344/cm for the 6H and 4H polytypes, respectively. On the basis of the 29Si hyperfine structure and spin Hamiltionian parameters, the defect was deduced to consist of a pair of C vacancies in the (11▪0), or equivalent, planes.

The Carbon Vacancy Pair in 4H and 6H SiC. N.T.Son, P.N.Hai, A.Shuja, W.M.Chen, J.L.Lindström, B.Monemar, E.Janzén: Materials Science Forum, 2000, 338-342, 821-4