【Domestic Papers】Chongqing Institute of Green and Intelligent Technology——Advancements in Ga₂O₃-based heterojunction ultraviolet photodetectors: Types, fabrication techniques, and integrated materials for enhancing photoelectric conversion efficiency

      Researchers from the Chongqing Institute of Green and Intelligent Technology have published a dissertation titled "Advancements in Ga₂O₃-based heterojunction ultraviolet photodetectors: Types, fabrication techniques, and integrated materials for enhancing photoelectric conversion efficiency" in Journal of Alloys and Compounds.

Abstract

      Ga₂O₃-based heterojunction photodetectors integrate Ga₂O₃ with partner semiconductors via deposition techniques to obtain a high-quality interface, resulting in minimizing recombination losses and maximizing the external quantum efficiency of the device. Ga₂O₃-based heterojunction photodetectors enhance photoelectric conversion efficiency through the formed built-in electric field. Furthermore, the heterojunction photodetectors could operate in a self-powered mode, detecting light signals without external power sources. This review provides a comprehensive summary of the heterojunction types in Ga₂O₃-based photodetectors, covering both non self-powered (MSM) and self-powered (n-n, p-n, and p-i-n) configurations. It also details the geometric configurations, including planar, quasi-vertical, and vertical types. In addition, the review also provides an overview of various fabrication techniques employed for these photodetectors, including chemical vapour deposition, magnetron sputtering, mechanical exfoliation, and molecular beam epitaxy. The materials utilized in fabricating Ga₂O₃-based heterojunctions photodetector are also discussed, encompassing doped Ga₂O₃, nitride, graphene, MXenes, oxides, chalcogenides, organic materials, and perovskites. The review further addresses the challenges and future directions for Ga₂O₃-based heterojunctions. Future research is anticipated to focus on enhancing the quality of Ga₂O₃ crystals, exploring new materials for heterojunction construction, increasing lattice matching, and developing ultrathin devices. The key priority is to propose an enhanced strategy to address the challenges encountered by Ga₂O₃-based heterojunction photodetectors in practical applications (environmental monitoring, space exploration, industrial process monitoring, biomedical imaging, defense and security). In conclusion, creating heterojunctions is an effective approach to significantly enhance the photoelectric conversion efficiency of UV photodetectors.