Identification of trapping defects in 4H -silicon carbide metal-insulator-semiconductor field-effect transistors by electrically detected magnetic resonance

In conventional SiSi O2 -based metal oxide semiconductor devices, performance-limiting semiconductor/dielectric interface traps are localized precisely at the SiSi O2 boundary. The authors show that in high-quality SiCSi O2 -based devices, this is not necessarily the case. Magnetic resonance and electrical measurements indicate that in relatively high quality 4H-SiC metal-insulator-semiconductor field-effect transistors, there exist relatively high concentrations of intrinsic deep level defect centers extending below the SiCSi O2 interface into the SiC bulk. The primary defect observed is almost certainly an intrinsic defect of high symmetry, most likely a silicon vacancy center.