Deep Ultraviolet Detector Based on Low-Temperature Fabricated ZnO/Ga2O3 Heterojunction

Abstract

The day-blind ultraviolet detector has been widely recognized due to its enormous potential in military and civilian applications such as missile tracking, flame detection, and electrical grid security. In comparison to the narrow bandgap semiconductor material Si, amorphous Ga 2 O 3 is possessed of an ultra-wide bandgap, high-temperature resistance, high-pressure resistance, and the advantage of lowtemperature and low-cost preparation, making it an ideal material for day-blind ultraviolet detectors. In this study, sol-gel and magnetron sputtering methods were employed to fabricate Ga 2 O 3 /ZnO heterojunction deep ultraviolet detectors. Compared to pure Ga 2 O 3 detectors, a reduction in dark current by an order of magnitude was observed in the Ga 2 O 3 /ZnO heterojunction detectors. The photocurrentto-dark current ratio increased by approximately 50 times, and the responsiveness increased by nearly an order of magnitude, resulting in a lower detection rate. This improvement can be attributed to the Ga 2 O 3 /ZnO heterojunction. Additionally, detector arrays were prepared, and the uniformity of the fabricated thin films was verified.