Fast-response solar-blind ultraviolet photodetector with a graphene/β-Ga2O3/graphene hybrid structure

A high performance vertical solar-blind ultraviolet photodetector based on β-Ga2O3 thin films sandwiched between two graphene sheets has been fabricated by laser molecular beam epitaxy. The photodetector exhibits obvious rectifying characteristics and excellent solar-blind UV photoresponse. The fast rising and decay time of our detector are 0.96 s and 0.81 s under 254 nm illumination. The ratio of I254/Idark is up to 82.88 and the responsivity of graphene/β-Ga2O3/graphene photodetector increases to 9.66 A/W at 10 V bias. Our results suggest that this performance is attributed to the existence of Schottky barriers between β-Ga2O3 and two graphene sheets. The combination of Ga2O3 and graphene might open up new possibilities for future UV integrated optoelectronic devices.