High-Performance 4H–SiC-Based Metal–Insulator–Semiconductor Ultraviolet Photodetectors With $hbox{SiO}_{2}$ and hbox{Al}_{2}hbox{O}_{3}hbox{/}hbox{SiO}_{2}$ Films

摘要

4H-SiC-based metal–insulator–semiconductor (MIS) ultraviolet (UV) photodetectors with thermally grown $hbox{SiO}_{2}$ and evaporated $hbox{Al}_{2}hbox{O}_{3}hbox{/}hbox{SiO}_{2}$ (A/S) films are fabricated and demonstrated as normally-off and normally-on mode devices, respectively. Ultralow dark currents of $hbox{3.25} times hbox{10}^{-10}$ and $hbox{9.75} times hbox{10}^{-9} hbox{A/cm}^{2}$ and high UV-to-visible rejection ratios of $>hbox{2} times hbox{10}^{3}$ have 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.