Electron spin resonance studies of transition metal deep level impurities in SiC.

By electron spin resonance (ESR) and photo-ESR, vanadium has been identified as an electrically amphoteric deep level impurity introducing both donor, Dhigh0/Dhighplus, and acceptor, Ahigh0/Ahighminus, states in the band gap of 4H- and 6H-SiC. The vanadium donor level in 6H-SiC has been located by photo-ESR near midgap, Esubv plus 1.6eV. Omnipresent titanium impurities were found to form complexes with nitrogen donors; the corresponding donor level of the (TiN) pair in 6H-SiC occurs at Esubc-0.6eV.