Sol-Gel Synthesized Amorphous (In_xGa_1-x)₂O₃ for UV Photodetection with High Responsivity

β-Ga₂O₃ photodetectors have the advantages of low dark current and strong radiation resistance in UV detection. However, the limited photocurrent has restricted their applications. Herein, MSM UV photodetectors based on (In_xGa_1-x)₂O₃ (x = 0, 0.1, 0.2, 0.3) by a sol-gel method were fabricated and studied. The doping of indium ions in Ga₂O₃ leads to lattice distortion and promotes the formation of oxygen vacancies. The oxygen vacancies in (In_xGa_1-x)₂O₃ can be modulated by various proportions of indium, and the increased oxygen vacancies contribute to the enhancement of electron concentration. The results show that the amorphous In_0.4Ga_1.6O₃ photodetector exhibited improved performances, including a high light-to-dark current ratio (2.8 × 10³) and high responsivity (739.2 A/W). This work provides a promising semiconductor material In_0.4Ga_1.6O₃ for high-performance MSM UV photodetectors.