Simply equipped ε -Ga 2 O 3 film/ZnO nanoparticle heterojunction for self-powered deep UV sensor

Abstract In this paper, a ε -Ga 2 O 3 film/ZnO nanoparticle hybrid heterojunction deep ultraviolet (UV) photodetector is described for 254 nm wavelength sensing application. The constructed ε -Ga 2 O 3 /ZnO heterojunction photodetector can operate in dual modes which are power supply mode and self-powered mode. Under reverse 5 V bias with 254 nm light intensity of 500 μ W cm −2 , the photoresponsivity, specific detectivity and external quantum efficiency are 59.7 mA W −1 , 7.83 × 10 12 Jones and 29.2%. At zero bias, the advanced ε -Ga 2 O 3 /ZnO photodetector performs decent self-powered photoelectrical properties with photo-to-dark current ratio of 1.28 × 10 5 , on/off switching ratio of 3.22 × 10 4 , rise/decay times of 523.1/31.7 ms, responsivity of 4.12 mA W −1 and detectivity of 2.24 × 10 12 Jones. The prominent photodetection performance lays a solid foundation for ε -Ga 2 O 3 /ZnO heterojunction in deep UV sensor application.