Robust and fast response solar-blind UV photodetectors based on the transferable 4H-SiC free-standing nanowire arrays

Wide band gap semiconductor 4H-SiC has been considered as the most promising candidate for developing solar blind ultraviolet (UV) photodetectors (PDs). However, the absence of PDs constructed by the desired 4H-SiC nanostructures greatly limits their performance and practical application. In this study, the free-standing 4H-SiC bamboo-like nanowire arrays with an even diameter/height of 30 nm/35 µm prepared by the anodic oxidation of 4H-SiC bulk single crystal in a top-down manner are used to develop the solar-blind PDs. Experiment results reveal that the developed PDs can have an excellent solar-blind detection performance such as high sensitivity to 275 and 365 nm UV light, a considerable light-dark ratio (∼44.3), remarkably low dark current, fast response (47.3 ms), excellent repeatability and stability. Additionally, the unencapsulated PDs can have an excellent high-temperature stability up to 300 ºC. It is expected that the 4H-SiC nanowire arrays-based PDs can have more potential than their counterpart bulk material for the future optoelectronic device applications.