Efficient Assembly of Bridged β-Ga2O3 Nanowires for Solar-Blind Photodetection

An increasing number of applications using ultraviolet radiation have renewed interest in ultraviolet photodetector research. Particularly, solar-blind photodetectors sensitive to only deep UV (<280 nm), have attracted growing attention because of their wide applicability. Among recent advances in UV detection, nanowire (NW)-based photodetectors seem promising, however, none of the reported devices possesses the required attributes for practical solar-blind photodetection, namely, an efficient fabrication process, a high solar light rejection ratio, a low photocurrent noise, and a fast response. Herein, the assembly of beta-Ga2O3 NWs into high-performance solar-blind photodetectors by use of an efficient bridging method is reported. The device is made in a single-step chemical vapor deposition process and has a high 250-to-280-nm rejection ratio (similar to 2 x 10(3)), low photocurrent fluctuation (<3%), and a fast decay time (20 ms). Further, variations in the synthesis parameters of the NWs induce drastic changes in the photoresponse properties, which suggest a possibility for tuning the performance of the photodetectors. The efficient fabrication method and high performance of the bridged beta-Ga2O3 NW photodetectors make them highly suitable for solar-blind photodetection.