Preparation And UV Detection Properties Of Gallium Oxide Thin Films And Their Heterojunctions

Ultraviolet light has been widely used.How to detect and control ultraviolet light accurately is important.Gallium oxide(Ga₂O₃)is considered to be the preferred material for 250?320 nm ultraviolet detectors due to 4.6?5.3 e V bandgap and high UV Vis absorption ratio.It has chemical properties and no toxicity.It has been widely used due to its various epitaxial layer preparation methods.The high baligan value and breakdown electric field make it have great potential in high power electronic devices.At present,the preparation cost of homogeneous substrate of Ga₂O₃ is very high,and the preparation size is not enough,so heteroepitaxial thin films have gradually become a hot spot.However,Preparing high-quality films is difficult and needs more research.The films with poor crystallinity show high resistance characteristics and low response.In this paper,the process parameters of gallium oxide were systematically studied.Then,we prepared heterojunction of Ga₂O₃/MgZnO and its UV detection performance was studied.Firstly,the basic parameters and process window of Ga₂O₃ grown by RF magnetron sputtering were studied.In order to study the effect of different process parameters on the quality of Ga₂O₃ crystal,the crystal structure and crystal orientation of Ga₂O₃ samples grown with different process parameters were studied by XRD and Raman spectroscopy.The morphology of Ga₂O₃ samples was analyzed by SEM and AFM.Optical properties studied by UV spectroscopy.The best data is 0.8 Pa,pure argon,100 W power and 120 min.Secondly,the effects of heat treatment(substrate growth temperature and annealing after sputtering at room temperature)on the crystal structure,surface morphology and optical properties of the films were studied.When temperature increased,the crystalline quality of the films increases and the grain size increases.Comparing the two groups of experiments,it is concluded that 750?substrate temperature is the best growth condition.Finally,we fabricated Ga₂O₃/MgZnO heterojunction and studied its solar blind UV detection performance.The interdigital electrode(Ti+Au)was prepared by using metal mask in vacuum evaporation machine to make MSM type UV detector.The test results show that the detector is photoconductive.The photocurrent of the device is1.75 m A and the ratio of light to dark is 20:1 under -10V bias.