Preparation And Characterization Of(Ga_1-xIn_x)₂O₃ Films By Magnetron Sputtering

Gallium oxide(Ga2O3)material,as a representative of new wider band gap semiconductors,has important application potential in the fields of ultraviolet detection and high frequency power devices due to its excellent chemical,physical and photoelectric properties.However,Ga2O3 is limited in many applications due to its large band gap(4.9eV).Considering that the alloy material of(Ga1-xInx)2O3 can adjust the band gap width by adjusting its composition,it can better play the role of band engineering in Ga2O3-based high-power electronic devices and ultraviolet photoelectric detection,which has become one of the research hotspots in the field of semiconductor materials in recent years.In this paper,(Ga1-xInx)2O3 thin films were prepared by magnetron sputtering.The effects of different In components,oxygen argon ratio and annealing process parameters on the properties of the films were studied.The main work and research results are as follows:1.The(Ga1-xInx)2O3 films with In composition in the range of 0～0.81 were prepared by double target co-sputtering.When the In composition x is 0.14～0.32,the main diffraction peak of(Ga1-xInx)2O3 films is β(002).When the In composition x is greater than 0.32,the main diffraction peak changes from β(002)to c(222).With the increase of In composition,the higher the proportion of In3+replacing Ga3+,the grain size of the film gradually increases,the absorption edge is red shifted,and the optical band gap is adjusted in the range of 4.94～3.42 eV.At the same time,When the In component increases from 0.14 to 0.81,the proportion of oxygen vacancies in the film increases from 17.6%to 64.6%.2.The effect of oxygen-argon ratio(O2:Ar)on the properties of(Ga1-xInx)2O3 thin films was systematically studied.It was found that with the increase of O2:Ar from 0:80 to 10:80,the number of oxygen vacancies decreased to a certain extent,which improved the quality of the films.The relative intensity of the β(002)diffraction peak gradually increased,the grain size gradually decreased,the surface roughness of the film gradually decreased,the transmittance gradually increased,the cutoff wavelength blue shifted,the Hall mobility and carrier concentration gradually increased,and the resistivity gradually decreased.However,when O2:Ar is further increased to 12:80,the proportion of argon ions in the chamber is relatively small,the number of atoms bombarding the target is reduced,and the deposition rate of the film is reduced,resulting in an increase in film defects and a decrease in quality.Based on the experiments carried out in this paper,the(Ga1-xInx)2O3 film prepared when O2:Ar is 10:80 has the best properties.3.The effects of annealing process parameters on the properties of(Ga1-xInx)2Ofilms were studied.It was found that with the increase of annealing temperature from 600℃ to 1000℃,the relative intensity of β(002)diffraction peak increased first and then decreased,the half peak width decreased from 3.31° to 0.44°,the grain size increased from 2.5 nm to 19.1 nm,the transmittance of the films increased gradually,and the absorption edge blue shifted.When the temperature rises to 1000℃,the stress release causes the film surface to crack and the crystal quality to decrease,and the corresponding performance test results also deteriorate.Based on the experiments carried out in this paper,when the annealing temperature is 900℃,the film has the best crystallinity,the smallest roughness,and the Hall effect test results show that the electrical properties are the best.