High-Performance4H-SiC-based metal-insulator-semiconductor ultraviolet photodetectors with SiO2 and Al2O3SiO2 Films

4H-SiC-based metal-insulator-semiconductor(MIS) ultraviolet(UV) photodetectors with thermally grown SiO2 and evaporated Al2}O3SiO}2(A/S) films are fabricated and demonstrated as normally-off and normally-on mode devices, respectively. Ultralow dark currents of3.25\times10}-10 and9.75\times10-9}\ A/cm}2 and high UV-to-visible rejection ratios of2}\times10}3 have been achieved at10 V. The peak responsivities of these devices were separately30 mA/W at260 nm and50 mA/W at270 nm at10 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.?2006 IEEE.