Ga2O3薄膜的常温磁控溅射制备对其结构及光学特性的影响  

Microstructures and Optical Properties of Ga2O3 Coatings Synthesized by Magnetron Sputtering at Room Temperature

作　　者：邵雨 蔡长龙[1] 杨陈[1] Shao Yu;Cai Changlong;Yang Chen(School of Optoelectronic Engineering,Xi'an Technological University,Xi'an 710021,China)

机构地区：[1]西安工业大学光电工程学院

出　　处：《真空科学与技术学报》2019年第12期1096-1101,共6页Chinese Journal of Vacuum Science and Technology

基　　金：陕西省科技厅重点产业创新链项目(项目编号:2018ZDCXL-GY-08-02-01);陕西省教育厅重点实验室科研计划项目(项目编号:17JS046);陕西省教育厅重点实验室科研计划项目(项目编号:17JS049);西安市智能探视感知重点实验室项目(项目编号:201805061ZD12CG45)

摘　　要：本文通过常温射频磁控溅射在单抛硅片和石英玻璃基底上溅射制备Ga2O3薄膜。采用分光光度计和椭偏仪测试薄膜的紫外光波段的透过率、折射率和光学吸收,利用X射线光电子能谱(XPS)测试了不同氧气氛下Ga2O3薄膜中氧元素的化学价态及其含量,X射线衍射(XRD)测试和拉曼散射光谱测试研究退火对薄膜生长及晶相结构的影响,采用微控四探针测试仪测试了薄膜的电阻率。研究了溅射功率、氩氧比、退火等工艺参数对薄膜结构及光电性能的影响。研究发现经过常温溅射后,再经过后退火处理的薄膜,无论在结构还是光学性能都优于之前传统制备工艺。结果显示:在氩氧比为80∶20、溅射功率为175 W、压强1.5 Pa条件下溅射2 h,沉积的薄膜厚度为197.6 nm,在紫外光波段吸收峰在284 nm,峰值透过率达到92.82%。在900℃退火下,薄膜的导电性能最好,电阻率达到137.21 m·cm。XRD测试和拉曼散射光谱结果表明,随着退火温度的升高,薄膜表现出择优生长趋势,发现β-Ga2O3的(201)、(401)和(403)的衍射峰随着退火温度的增加进一步增强。利用Tauc公式由透过率数据计算光学带隙结果表明,随着退火温度升高薄膜光学带隙由在4.93~5.28 eV范围内变化。The Ga2O3 thin films were synthesized by RF magnetron sputtering at room temperature on substrates of Si-wafer and quartz-glass.The influence of the Ar/O2 flow-rate ratio and annealing temperature on the microstructures and optical properties of "cold-deposited" Ga2O3 coatings was investigated.The results show that an O2-addition and post-annealing significantly improved the microstructures and optical properties of the conventional hot-deposited Ga2O3 coatings.For example,cold-deposited at 175 W and Ar/O2 flow-rate ratio of 80∶20,the 197.6 nm thick Ga2O3 coatings,annealed at 900℃,had an absorption peak at 284 nm in ultraviolet band,a transmittance peak of 92.82%,and a resistivity of 137.21 m·cm.As the annealing temperature increased from 700℃ to 1000℃,the optical band-gap decreased from 5.28 to 4.93 eV,and the preferential growth of β-Ga2O3 grains,in <201>,<401> and <403> orientations,became increasingly pronounced.

关 键 词：磁控溅射 Ga2O3薄膜 X射线衍射 拉曼散射 光学带隙 

分 类 号：TN04[电子电信—物理电子学] TB34[一般工业技术—材料科学与工程]