Metalorganic Chemical Vapor Deposition Heteroepitaxial β-Ga2O3 and Black Phosphorus Pn Heterojunction for Solar-Blind Ultraviolet and Infrared Dual-Band Photodetector

Recently, beta-Ga2O3 and black phosphorus (BP) have attracted enormous attention as the solar-blind ultraviolet (UV) and infrared (IR) photosensitive materials for next-generation optoelectronic devices, respectively, due to their special bandgap and electrical characteristics. Many beta-Ga2O3-based UV photodetectors and BP-based IR photodetectors have been investigated separately, but there is no report on the heterojunction and photoelectric devices formed by these two excellent materials. Herein, metalorganic chemical vapor deposition (MOCVD) heteroepitaxial beta-Ga2O3 and BP pn heterojunction for solar-blind UV and IR dual-band photodetector is proposed and demonstrated for the first time. The device demonstrates a remarkable photoresponse under UV and IR irradiations with a responsivity of 88.5 and 1.24 mA W-1, respectively, clear pn heterojunction characteristics, as well as an excellent photoswitch periodicity. Moreover, under different irradiation conditions, the photoelectric properties of beta-Ga2O3/BP pn heterojunction, including their photogeneration and photoresponse, are investigated in detail. These results signify that beta-Ga2O3/BP pn heterojunction may find potential applications in future UV/IR dual-band detection systems.