Research On Photoelectric Detection Devices Of Gallium Oxide/zinc Oxide Heterojunction

Due to the absorption of the Earth's ozone layer on ultraviolet radiation(200-280 nm region),the solar-blind ultraviolet photodetector working has a great advantage in sensitivity.It has a wide application prospect in many fields,such as solar-blind ultraviolet communication,quantum information,missile warning,space exploration,corona detection,environmental monitoring and biomedical medicine.?-Ga2O3 as a kind of wide-band semiconductor material,has a direct band gap,its energy gap is 4.2-4.9 eV,the corresponding photon wavelength is 253 nm-295 nm,is a natural solar-blind ultraviolet detection materials,so in recent years gallium oxide has received more and more attention.Compared to photoelectric detectors based on single material,photoelectric detectors based on heterojunction structure has many advantages,and it is also a research hotspot in recent years.In this paper,Heterojunctions composed of ?-Ga2O3 and ZnO films were vertically fabricated on sapphire substrates using laser molecular beam epitaxy method and magnetron sputtering technology.X-ray diffraction(XRD)was used to characterize the crystal structure and photoelectric response was measured.The main research results are as follows:1.By comparing the XRD patterns of the heterojunction that was grown by two different methods,we believe that the L-MBE method grows the better heteroj unction.2.The heterojunction present excellent rectifying characteristic with an asymmetry ratio over 105 by photoelectric response test.Prominent solar-blind photoresponse effect was also observed in the formed heterojunction.The photodetector exhibits a self-powered behavior with a fast response speed(rise/decay time:0.035 s/0.032 s)at zero bias.3.An energy band analysis of its photoelectric characteristics shows that the performance of its high-speed response is related to the build-in field driven photogenerated electron-hole separation.