Self-Powered Solar-Blind Photodetector with Fast Response Based on Au/β-Ga2O3 Nanowires Array Film Schottky Junction

Because of the direct band gap of 4.9 eV, beta-Ga2O3 has been considered as an ideal material for solar-blind photodetection without any bandgap tuning. Practical applications of the photodetectors require fast response speed, high signal-to-noise ratio, low energy consumption and low fabrication cost. Unfortunately, most reported beta-Ga2O3-based photodetectors usually possess a relatively long response time. In addition, the beta-Ga2O3 photodetectors based on bulk, the individual 1D nanostructure, and the film often suffer from the high cost, the low repeatability, and the relatively large dark current, respectively. In this paper, a Au/beta-Ga2O3 nanowires array film vertical Schottky photodiode is successfully fabricated by a simple thermal partial oxidation process. The device exhibits a very low dark current of 10 pA at 30 V with a sharp cutoff at 270 nm. More interestingly, the 90-10% decay time of our device is only around 64 Its, which is much quicker than any other previously reported beta-Ga2O3-based photodetectors. Besides, the self-powering, the excellent stability and the good reproducibility of Au/beta-Ga2O3 nanowires array film photodetector are helpful to its commercialization and practical applications.