High-performance self-powered UV photodetector based on CuI/CsCu2I3/GaN heterojunction

Self-powered ultraviolet (UV) photodetectors have far-reaching applications in the nanoelectronics. In this work, nontoxic copper halide perovskite CsCu2I3 thin films were grown by vacuum thermal evaporation method on n-GaN substrates. The p-CuI/CsCu2I3/n-GaN heterojunction photodetectors exhibit obvious sensitivity and self-powered characteristics in the ultraviolet (similar to 365 nm) narrowband. The device exhibits excellent reproducibility and a high on/off ratio of 97,886 under zero bias voltage. Furthermore, under UV illumination, the responsivity, specific detectivity, and external quantum efficiency reach 71.7 mA/W, 3.3 x 10(12) Jones, and 26.1% at 0 V bias, respectively. The result provides a new strategy to design a highly integrated monolithic device for self-powered detection

Automated summary

This study successfully grows nontoxic copper halide perovskite CsCu2I3 thin films and develops self-powered ultraviolet photodetectors with significant sensitivity and high on/off ratio. Under UV illumination, the responsivity and external quantum efficiency reach a high level.