Recent advances in heterojunction engineering of β -Ga 2 O 3 -based solar-blind ultraviolet photodetectors

Abstract In recent years, the demand for high-performance photodetectors in environmental monitoring, specialized detection, and space communications has grown significantly. Solar-blind ultraviolet (SBUV) photodetectors have become a research hotspot due to their unique spectral selectivity and high sensitivity. As an ultra-wide bandgap semiconductor material (∼4.9 eV), β -Ga 2 O 3 is regarded as a highly promising material for SBUV detection owing to its excellent intrinsic properties, including high breakdown field strength, outstanding thermal stability, and superior response in the SBUV band. Research demonstrates that constructing β -Ga 2 O 3 -based heterojunctions effectively regulates interfacial band structures, significantly enhances photogenerated carrier separation efficiency, improves device responsivity while suppressing dark current, and offers potential pathways to address performance limitations of conventional photodetectors. Based on a coordinated material-device optimization framework, this review systematically summarizes recent research advances in β -Ga 2 O 3 heterojunction SBUV photodetectors, with a focus on performance optimization strategies from three dimensions: material property modulation, heterojunction interface engineering, and device structure design. Future development directions are also discussed.