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 Ga₂O₃ is possessed of an ultra-wide bandgap, high-temperature resistance, high-pressure resistance, and the advantage of low-temperature 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 Ga₂O₃/ZnO heterojunction deep ultraviolet detectors. Compared to pure Ga₂O₃ detectors, a reduction in dark current by an order of magnitude was observed in the Ga₂O₃/ZnO heterojunction detectors. The photocurrent-to-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 Ga₂O₃/ZnO heterojunction. Additionally, detector arrays were prepared, and the uniformity of the fabricated thin films was verified.

Guanhua Wu, Junlin Fang, Zhenhua Tang. Deep Ultraviolet Detector Based on Low-Temperature Fabricated ZnO/Ga₂O₃ Heterojunction. Academic Journal of Materials & Chemistry (2024) Vol. 5, Issue 1: 1-6. https://doi.org/10.25236/AJMC.2024.050101.

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