The Photoelectric Characteristics Of Doped Ga₂O₃Films With L-MBE Method

It is a hotspot reaserch that doped a few percent of metal ion into semiconductormaterirals in21st century. we can get P-type or N-type semiconductor by doping withdifferent metal ions. Ga₂O₃is an interesting direct wide bandgap semiconductor oxidematerials that is being explored for numerous application.Because of the hightransmitence in deep ultraviolet and visible light that the application of optoelectronicdevices is expected, such as Ga based semiconductor material insulating layer,UV filter,O2chemical detector and so on.1. In this paper preparation methods, properties and applications of Ga₂O₃films weresummarized.High quality gallium oxide deep UV transparent film was prepared by lasermolecular beam epitaxy method.During the preparation process, we reserched theinfluence of different oxygen partial peressure,laser energy,substrate temperature on thesurface morphology,crystal quality of the gallium films.We fund the best growthconditions:laser energy is200mJ,oxygen partial pressure is1Pa,background vacuum5×10^-5Pa,target-substrate is5cm,the substrate temperature is675℃2. With the same preparation method,β-Ga₂O₃film with ZnO nano-interlayer wasprepared,and the characteristics of the film were researched.We got three different filmsby changing the sputtering time of ZnO nano interlayer.The XRD, SEM,UVtransmission,forbidden band width and PL were researched. Constrasted withβ-Ga₂O₃film,the GZO film’s transmittance was below than Ga₂O₃film in UV region, ZnO nonainterlayer makesβ-Ga₂O₃film’s band gap appear blue shift, PL spectrum display thatthe GZO and Ga₂O₃film’s luminescence center at384nm and427nm, both of them haveblue luminescence properties.3. In order to make the gallium oxide thin film get better application,we prepared theSn-doped and Cu-doped gallium oxide films with double target sputtering method, andthen annealled to mix the impurity atoms.（1）.With the different sputtering times of Sn target,we obtained different concentrationsSn-doped β-Ga₂O₃films and did various tests. The influence of β-Ga₂O₃film’sstructure and optical properties were studied.From the SEM, XRD, XPS,Raman,UV-Transmission and bandgap width test results we found that with the increase of Snsputtering time （Sn doping concentration increased）, thin film transmission increasedgradually, in deep ultraviolet area is over80%, and makes the film can better used inphotoelectric devices.（2） We fabricated Cu-doped β-Ga₂O₃films With the same method.We obtained differentCu concertration β-Ga₂O₃films by different sputtering time of Cu target.The sametests were did as Sn-doped β-Ga₂O₃films.The influence of β-Ga₂O₃film’s structure and optical properties were studied.XRD results showed that Cu doping maked the film’sgrowth direction and grain size changed.SEM surface topography showed that Cudoping maked the surface appeared large particles, UV transmission specturm showedthat with the increase of Cu concentation the transmission gradually reduced, theforbidden band width decreased,and the absorption peak appeared red shift phenomenon,Raman specturm showed that Raman vibration decreased.