Highly Reliable and Sensitive Solar-Blind Ultraviolet and X-Ray Detector Based on ALD Deposited Amorphous Ga₂O₃

This study demonstrates a metal-semiconductor-metal (MSM) type photodetector based on 50 nm amorphous Ga₂O₃ film using the atomic layer deposition (ALD) technique that can provides effective detections at both solar-blind and X-ray lights. The detector exhibits stable performances at high temperature ( $150~^{\circ }$ C) in the air, characterized by a low dark current (<0.1 nA), high photo-to-dark current ratio ( $\gt 10^{{5}}\text {)}$ , and fast responses (rising/decaying times of 0.53/0.13 s), respectively. Meanwhile, the detector shows the high sensitivity ( $952~\mu $ C Gy $_{\text {air}}^{-{1}}$ cm $^{-{2}}\text {)}$ and ultra-low detection limit (11.23 nGy_airs $^{-{1}}\text {)}$ in X-ray detection, which is among the highest values reported in Ga₂O₃ thin film photodevices to the best of authors’ knowledge. The superior capabilities can be ascribed to the restricted oxygen vacancies during the ALD process. These results indicate that the Ga₂O₃-based detector has great potential for applications in security system and irradiation exploration in harsh environments.