Self-powered solar-blind ultraviolet photodetectors with Ga2O3 nanowires as the interlayer

Abstract

Solar-blind photodetectors are widely used in military, industrial and commercial fields. There is an urgent need to develop devices with high spectral selectivity, high performance and low energy consumption. Here, ultrafine β-Ga2O3 nanowires were synthesized on a n-Si substrate using chemical vapor deposition, and a self-powered solar-blind photodetector based on β-Ga2O3 nanowires cluster and n-Si were fabricated with PEDOT:PSS as a transparent conductive layer to spread the current. Additionally, PMMA was used as an insulating layer to prevent short circuiting of the device and the device fabrication process was described in detail. In the aforementioned PEDOT:PSS/Ga2O3NWs/Si double heterojunction device, Ga2O3 nanowires serve as vital spectral-selective materials for the solar-blind band. The significance of Ga2O3 nanowires as an interlayer within the device was explored by introducing nanowires with varying morphologies. The inclusion of Ga2O3 nanowires led to a substantial improvement in the device's responsivity within the solar-blind band, while the performance within the visible band remained relatively unchanged. Remarkably, at a wavelength of 250 nm, the device incorporating a cluster of Ga2O3 nanowires as the interlayer exhibited a responsivity of 26.8 mA/W, which is 44 times greater than that of the PEDOT:PSS/Si heterojunction device.