【Device Papers】High-Speed Response Perovskite/α-Ga₂O₃ Heterojunction Self-Powered Deep Ultraviolet Photodetector

      Researchers from Hubei University have published a dissertation titled " High-Speed Response Perovskite/α-Ga₂O₃ Heterojunction Self-Powered Deep Ultraviolet Photodetector " in Journal of Materials Chemistry C.

Abstract

      Ga₂O₃ is endowed with a unique capability for application in commercial solar-blind photodetectors. However, the relatively slow response speed of Ga₂O₃-based photodetectors has limited their integration and application. This study demonstrates a vertical photodetector based on a CsPbBr₃/α-Ga₂O₃ heterostructure, which was fabricated using a facile and low-cost solution-processing method. The device exhibits rise and fall times of 7 and 10 ms, respectively, at zero bias, which are three orders of magnitude faster than those of pure α-Ga₂O₃ photodetector. Under weak light intensity (50 µW cm⁻²), the responsivity (R) is 22.41 mA W⁻¹, and the detectivity (D^*) is 3.74 × 10¹¹ Jones at zero bias. Without encapsulation, the device still exhibits outstanding stability after 6 months of storage under ambient conditions. As a light absorption layer, the CsPbBr₃ thin film enhances electron tunneling capability and accelerates the separation and recombination process of photogenerated carriers, which in turn improves the response speed. Meanwhile, a gradient band structure is formed between the CsPbBr₃ thin film and the α-Ga₂O₃ thin film, and the high-energy electrons in the conduction band of CsPbBr₃ are thermally excited to increase the carrier transfer efficiency. This work provides a feasible strategy for the industrialization of fast-response solar-blind photodetectors.

DOI：

https://doi.org/10.1039/D6TC00710D