The Ga₂O₃ photoconductor possesses a wide bandgap, a relatively large density and a high absorption coefficient for low-energy X-ray. Therefore, it is expected to realize a highly sensitive low-energy X-ray detector. Realizing p-n heterojunctions using Ga₂O₃ thin film is essential for large-area low-dose X-ray imaging. Here, a p-n diode consisting of nanocrystalline Ga₂O₃ thin film and NiO thin film is successfully prepared by electron beam evaporation, exhibiting a large current rectification ratio of 6.0 × 10⁴. The p-n heterojunction shows a large valence band offset of 1.7 eV, a large conduction band offset of 0.84 eV and a built-in potential of 0.2 eV near the interfacial region, benefiting for separation and migration of photogenerated carriers. In addition, the photoconductive gain mechanism of Ga₂O₃/NiO heterojunction based X-ray detectors with optimized NiO thickness is investigated, achieving a high internal gain (3.3 × 10³), a high sensitivity (3.4 × 10⁴ μCGy_air⁻¹ cm⁻²), a low detection limit (42 μGy_air s⁻¹) and a short response time (2.2 ms). The optimized detectors with 10 × 10 pixels show a uniform X-ray response, demonstrating their promising use in large-area X-ray imaging applications.

Ga ₂ O ₃光电导体具有宽带隙、较大的密度和对低能X射线的高吸收系数。因此，有望实现高灵敏度的低能X射线探测器。_{使用 Ga 2} O ₃薄膜实现 pn 异质结对于大面积低剂量 X 射线成像至关重要。_{在这里，通过电子束蒸发成功制备了由纳米晶Ga 2} O ₃薄膜和NiO薄膜组成的pn二极管，具有6.0×10 ^{4的大电流整流比。}. pn异质结具有1.7 eV的大价带偏移、0.84 eV的大导带偏移和0.2 eV的内建电位，有利于光生载流子的分离和迁移。此外，研究了具有优化NiO厚度的基于Ga ₂ O ₃ /NiO异质结的X射线探测器的光电导增益机制，实现了高内部增益（3.3 × 10 ³）、高灵敏度（3.4 × 10 ⁴ μCGy _air ^{- 1} cm ^-2），低检测限（42 μGy _air s ^-1) 和较短的响应时间 (2.2 ms)。具有 10 × 10 像素的优化探测器显示出均匀的 X 射线响应，证明了它们在大面积 X 射线成像应用中的应用前景。