High-Performance 4H–SiC-Based Metal–Insulator–Semiconductor Ultraviolet Photodetectors With SiO₂ and Al₂O₃/SiO₂ Films

4H-SiC-based metal-insulator-semiconductor (MIS) ultraviolet (UV) photodetectors with thermally grown SiO2and evaporated Al2O3/SiO2(A/S) films are fabricated and demonstrated as normally-off and normally-on mode devices, respectively. Ultralow dark currents of 3.25 × 10-10and 9.75 × 10-9A/cm2and high UV-to-visible rejection ratios of >; 2 × 103have been achieved at 10 V. The peak responsivities of these devices were separately 30 mA/W at 260 nm and 50 mA/W at 270 nm at 10 V. These results demonstrate that S/4H-SiC and A/S/4H-SiC MIS photodetectors are promising candidates to be applied in optoelectronic integrated circuits.