Development and Challenges of Ga2O3–Based Heterojunctions for Deep-UV Detectors

Deep-ultraviolet (DUV) detectors have attracted increased attention recently for applications such as missile guidance and secure satellite communication. As one of the emerging ultrawide bandgap semiconductors, gallium oxide (Ga 2 O 3 ) is sensitive to most of the solar-blind band of the solar spectrum and is considered an ideal material for DUV detectors. Heterojunction photodetectors offer the advantages of low dark current, fast response, large current switching ratio, and significant internal electric fields, making them ideal candidates for Ga 2 O 3 photodetectors. This review comprehensively summarizes the recent progress on emerging heterojunction DUV detectors based on Ga 2 O 3, highlighting the fundamental physics, key parameters, and their relation to material properties. The review also critically examines the diverse heterojunction architectures (e.g., p–n, p–i–n) being explored with Ga 2 O 3, correlating their design with resultant detector performance metrics. Furthermore, we discussed potential future applications of Ga 2 O 3 heterojunction-based DUV photodetectors in specialized fields. The challenges that limit device performance and present roadblocks to commercialization are also discussed, with potential solutions to these challenges explored.