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 effi cient fabrication process, a high solar light rejection ratio, a low photocurrent noise, and a fast response. Herein, the assembly of β -Ga 2 O 3 NWs into high-performance solar-blind photodetectors by use of an effi cient 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 ( ∼ 2 × 10 3 ), low photocurrent fl uctuation ( < 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 effi cient fabrication method and high performance of the bridged β -Ga 2 O 3 NW photodetectors make them highly suitable for solar-blind photodetection.

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