▎ 摘　　要

Gallium oxide semiconductor, with a bandgap energy of 4.9 eV, is regarded as a hopeful candidate for next-generation solar-blind photodetectors. However, the construction of photodetector based on Ga2O3 pn junction is still challengeable due to immature doping technology of p-Ga2O3. By considering the small lattice mismatch (<3%) and similar band gap structure of alpha-Ga2O3 and beta-Ga2O3, a well-designed solar-blind photodetector was built, based on vertical alpha/beta-Ga2O3 junction nanorod arrays (NRAs) with a graphene-silver nanowires (Ag NWs) hybrid top electrode. Thanks to the high conductivity and optical transmittance of graphene-Ag NWs top electrode, the photodetector based on alpha/beta-Ga2O3 junction NARs displayed excellent photoelectric performance. Meanwhile, the matched band structure of P type formed at the interface of alpha/beta-Ga2O3 junction promoted the automatic separation of photogenerated carriers and their transfer to the corresponding electrodes. A fast photoresponse time of 0.54 s, a high light-to-dark ratio about 2000, and a high rejection ratio (R-254/R-365) of 2.7 x 10(3) under the zero bias, were realized. The excellent photoelectrical performance of alpha/beta-Ga2O3 junction photodetector even in vacuum environment forecasts its potential application in some low air density fields, such as missile early warning and tracking and ozone hole monitoring. (c) 2020 Elsevier Ltd. All rights reserved.