In order to investigate defects in n-doped 6H-type single crystals, as produced by neutron bombardment, electron spin resonance measurements were performed on neutron-irradiated samples during annealing at up to 1400C. Six centres (K1 to K6), which arose from radiation-induced defects, were observed in the electron spin resonance spectra at liquid-N temperatures. The main K1 centre originated from a Si vacancy. The angular dependences of the K2, K3 and K4 centres, with an effective spin of S = 1, could be described in terms of 2 electron spins which interacted with each other. The results suggested that the K2, K3 and K4 centres originated in complexes which were related to the Si vacancy. These centres exhibited various isochronal annealing behaviours. The K3 centre annealed out at 200C, while the K1 and K2 centres annealed out at around 800C.

Electron Spin Resonance in Neutron-Irradiated n-type 6H-Silicon Carbide. S.Kanazawa, I.Kimura, M.Okada, T.Nozaki, I.Kanno, S.Ishihara, M.Watanabe: Materials Science Forum, 2000, 338-342, 825-8