高阻紫外光阴极导电基底制备及性能

Growth and Properties of Conductive Substrates of Ultraviolet Photocathode with High Resistance

在MgF2基片上,采用电子束蒸发镀膜法制备了掺锡氧化铟（ITO）导电基底,研究了充氧及退火对ITO薄膜电阻及紫外透射比的影响。并与传统的金属导电基底Au和Cr进行了性能比较。用光学显微镜、四探针测试仪、高阻计、X射线衍射仪（XRD）和分光光度计分别测试了薄膜的表面形貌、方块电阻、形态结构和190～800 nm波段范围内薄膜的透射比曲线,得到方块电阻为10^7Ω左右时薄膜在200～400 nm波段内透射比的变化范围。实验结果表明,厚度相同时,充氧会增大ITO薄膜电阻;退火则会降低薄膜电阻并提高紫外透射比,薄膜结构由非晶态变为多晶态。方块电阻同为10^7Ω时,在200～400 nm波段充氧退火后ITO薄膜的平均透射比比Au,Cr的高10%。

Tin-doped indium oxide（ITO） conductive thin film is prepared on MgF_2 substrate by electron beam evaporation.The effect of oxygen and annealing on the sheet resistance and ultraviolet（UV） transmittance of ITO film is investigated.Furthermore,the properties of ITO film are compared with conventional conductive film substrates Au and Cr.The surface morphological image,sheet resistance,microstructure and transmittance curves in the wave band of 190～800 nm are investigated by optical microscope（OM）,four-probe method,high resistance meter,X-ray diffractomer（XRD） and spectrophotometer.Variation range of transmittance is acquired in the wave band of 200～400 nm when the sheet resistance reaches 10~7Ω.The results indicate that the sheet resistance of thin film prepared with oxygen is higher than that without oxygen;after annealing the sheet resistance of thin film decreases and the microstructure changes from amorphous to polycrystalline.Compared to Au and Cr,the average transmittance of ITO film with the same sheet resistance of 10~7Ωor so,which is prepared with oxygen and annealing,is 10%higher in the wave band of 200～400 nm.