Nitride-based metal–insulator–semiconductor ultraviolet sensors with a sputtered lanthanum oxide (La2O3) insulator

This study reports the fabrication of GaN metal–insulator–semiconductor (MIS) ultraviolet (UV) sensors with an La2O3 insulating layer. With a 5 V applied bias, the leakage current of the fabricated MIS sensors with La2O3 insulating layers may be low to 4.95 × 10− 11 A. The dark current was substantially reduced, and the UV-to-visible contrast ratio was enhanced by inserting the La2O3 layer. Furthermore, the noise equivalent power was substantially reduced, and detectivity was enhanced by using La2O3 insulating layers.

► We fabricated GaN metal–insulator–semiconductor (MIS) ultraviolet (UV) sensors with a La2O3 insulating layer. ► We can significantly reduce dark current and enhance UV-to-visible contrast ratio by inserting the La2O3 layer. ► We can also reduce noise equivalent power and enhance detectivity by using La2O3 insulating layers.