Flexible Solar-Blind Ultraviolet Photodetector Based on β-Ga2O3 Nanowire Channel Bridge Structure: Combining High Responsivity and Strain Stability

Abstract

Solar-blind ultraviolet photodetectors are gaining attention for their high signal-to-noise ratio and strong anti-interference capabilities. With the rising demand for applications in high-strain environments, such as fire rescue robots and smart firefighting suits, a flexible photodetector that maintains stable performance under bending strain is needed. Current devices struggle to balance strain cycle stability and responsivity. This paper presents a β-Ga2O3 nanowire photodetector on a flexible ultra-thin silicon substrate, fabricated using microchannel engraving and chemical vapor deposition. The device achieves a responsivity of 266 mA W−1 without strain, with less than 5.5% variation in photogenerated current under bending strain (0–60°), and a response time of 360 ms. After 500 cycles of 60° bending, the photogenerated current changes by only 1.5%, demonstrating excellent stability and responsivity, with broad application potential in flame detection and biological sensing.