【Device Papers】Research Progress and Performance Enhancement Strategies for β-Ga₂O₃ Thin Film Solar-Blind Photodetectors

      Research team from Liaoning Normal University published an article titled “Research Progress and Performance Enhancement Strategies for β-Ga₂O₃ Thin Film Solar-Blind Photodetectors” in the academic journal China Surface Engineering.

Abstract

      Solar-blind ultraviolet (UV) photodetectors operating within the wavelength range of 200–280 nm have attracted increasing interest owing to their critical applications in military surveillance, environmental monitoring, space communication, and biomedical diagnostics. The unique feature of this spectral region is strong absorption by atmospheric ozone, which creates a natural solar-blind detection window. However, traditional silicon-based detectors require complex optical filters and suffer from high dark currents, low signal-to-noise ratios, and limited spectral selectivity, thereby failing to meet the requirements for high-precision detection. β-Ga₂O₃, which is a wide-bandgap semiconductor with a bandgap ranging from 4.2 to 4.9 eV, offers intrinsic solar-blind sensitivity, high thermal and chemical stability, and strong radiation hardness, thereby making it a highly promising candidate for next-generation solar-blind UV photodetectors. Among the five polymorphs of β-Ga₂O₃, the monoclinic β-phase is thermodynamically most stable and suitable for long-term operation in harsh environments. This review systematically outlines the recent advancements in the fabrication, device architectures, and performance optimization strategies of β-Ga₂O₃ thin-film-based solar-blind UV photodetectors. Four major deposition techniques are emphasized: magnetron sputtering, atomic layer deposition (ALD), mist chemical vapor deposition (Mist-CVD), and molecular beam epitaxy (MBE). Each technique is compared in terms of film crystallinity, deposition rate, uniformity, and cost-effectiveness. For instance, magnetron sputtering offers large-area deposition at a low cost, but typically yields amorphous or polycrystalline films, which require post-annealing. Despite the rapid development of β-Ga₂O₃-based solar-blind UV photodetectors, existing reviews have largely focused on material properties or individual device structures, while a systematic discussion spanning thin-film fabrication methods, device architectures, and performance optimization strategies remains limited. Therefore, this review comprehensively summarizes the preparation technologies, representative device configurations, and key approaches for performance enhancement of β-Ga₂O₃ thin-film solar-blind photodetectors, while also analyzing the major challenges and bottlenecks that currently restrict their practical deployment. From the integrated perspective of materials, structures, and device performance, a comprehensive research framework is established. Particular attention is devoted to the optimization of metal–semiconductor–metal (MSM) photodetectors and the integration of thin-film heterojunction architectures, which have emerged as effective routes toward higher responsivity, faster response speed, and improved spectral selectivity. By consolidating recent advances and identifying future research directions, this review broadens the understanding and application potential of β-Ga₂O₃ thin-film solar-blind photodetectors and provides valuable guidance for the development of next-generation high-performance ultraviolet sensing technologies.

Link：

https://kns.cnki.net/kcms2/article/abstract?v=yLAonKG4u-SUKHn_FwHrsSdUl1w1M5XGP8zPRrDkGhdzaNJBia-zpVL9-_qaxvmEeF_d2u95KaUMdgNMWY4QlzlymKo0qMvnUceE0irEksZih1QZCbeRyGZMxqbYcElba43ycR0IgowqBLyyOCprjfIuVQ7UgwpPFcDKDwtjE-BmZwtMCaIJ5g==&uniplatform=NZKPT&language=CHS