Electrical and optical characterisation of vanadium in 4H and 6H-SiC

Vanadium deep acceptor level in bulk 6H-SiC and 4H-SiC has been studied by deep level transient spectroscopy (DLTS), optical absorption (OA), photolum inescence (PL) and deep level optical spectroscopy (DLOS). DLTS reveals two levels related to vanadium acceptor level (V3 + /V4 +) for GH-SiC at E-c - 0.68 eV (cubic sites) and E-c - 0.74 eV (hexagonal site) and for 4H-SiC at E-c - 0.82 eV. The good correlation obtained between DLOS and OA spectra a llows us to identify OA lines and DLOS resonance band as V3+ internal trans ition between the (3)A(2) ground state towards excited states. The V3+ ion configuration in 4H-SiC is given. (C) 1999 Elsevier Science S.A. All rights reserved.