A Flexible UV Photodetector Based on ZnO/SiO 2 /PEDOTPSS Pin-Junction with Enhanced Wide UV Detection Capability

The development of flexible UV photodetectors (PDs) has always been a research hotspot in the field of optoelectronics. However, achieving wide UV spectral coverage while maintaining high responsivity and stability remains a challenge. We propose a novel device structure that integrates an SiO 2 film as an intrinsic layer into a ZnO/PEDOT:PSS [Formula: see text]–[Formula: see text] heterojunction to construct a [Formula: see text]–[Formula: see text]–[Formula: see text] heterojunction flexible PD. This PD is based on flexible polyethylene terephthalate (PET) and is fabricated using magnetron sputtering and spin-coating processes by sequentially depositing each functional film. At a 20[Formula: see text]V bias, the peak responsivity of ZnO/SiO 2 /PEDOT:PSS PD at 365[Formula: see text]nm is 390 times that of pure ZnO PD. The rise time and decay time corresponding to the response speed are 0.072[Formula: see text]s and 0.080[Formula: see text]s, respectively. The research results indicate that the spectral response range of the [Formula: see text]–[Formula: see text]–[Formula: see text] PD has been significantly broadened, successfully covering the 250–400[Formula: see text]nm range, achieving detection from UVC to UVA. The [Formula: see text]–[Formula: see text]–[Formula: see text] heterojunction can effectively broaden the depletion layer and optimize the electric field distribution, thereby achieving wide-spectrum detection and performance enhancement simultaneously. This provides a simple and effective strategy for the development of high-performance, broadband, flexible UV PDs.