Magnetic circular dichroism and electron spin resonance of the A- acceptor state of Vanadium, V3+, in 6H-SiC

The magnetic circular dichroism (MCD) of the absorption has been studied in a 6H-SiC crystal highly contaminated with vanadium, V. In addition to previously reported MCD absorption lines of V high4plus (3d high1), new sharp MCD lines have been observed near 2.0 mym. The chemical nature and origin of these lines were identified by MCD-detected electron spin resonance. They arise from V high3plus (3d high2) and most likely correspond to the high3 A sub2 about high3 T sub2 crystal field absorption. The positions of the V high3plus / V high4plus acceptor level and the V high4plus / V high5plus donor level are discussed. The possibility of growing high-resistivity SiC crystals by deliberate vanadium doping is pointed out.