Self-Powered Solar-Blind Photodetector With Low Dark Current and Ultrahigh On/Off Ratio Based on Vertically Aligned Si/SiC Nanowire Arrays p-n Heterojunction

Silicon carbide (SiC) 1-D nanoarray structures are the most promising architecture for developing high-performance ultraviolet photodetectors (UV PDs) due to their unique optoelectronic properties and large specific surface area. In pursuit of energy saving, high performance, robustness, and low-power consumption, SiC nanowire array (NWA)-based UV PDs with the ability of self-powered operation have gained more and more attention. In this study, SiC NWA-based vertical p-n junction self-powered UV PDs were successfully constructed with using 4H-SiC NWAs and Si NWAs. Experimental results demonstrated that the developed PDs can operate in the self-powered mode and exhibit remarkably low dark current (0.28 pA), a reasonably high photoresponse ON/OFF ratio (554.8), excellent responsivity ( $\sim$ 0.12 mA/W), fast photoresponse time (37.6/47.9 ms), and exceptional spectral selectivity ( $\sim$ 342.86). This study proposes a new strategy for developing self-powered SiC-based UV detectors for low-cost and high-performance optoelectronic devices.