TiO2薄膜基底上制作多碱光电阴极的探索研究  

Analysis of Multi Alkali Photocathode Deposition on TiO2 Film

作　　者：赵伟林 赵恒 曾进能 赵学峰[1] 常乐[1] 李廷涛[1] 李晓峰[1,2] ZHAO Weilin;ZHAO Heng;ZENG Jinneng;ZHAO Xuefeng;CHANG Le;LI Tingtao;LI Xiaofeng(North Night Vision Technology Co.Ltd,Kunming 650217,China;Science and Technology on Low-light-level Night Vision Laboratory,Xi’an 710065,China)

机构地区：[1]北方夜视技术股份有限公司,云南昆明650217 [2]微光夜视技术重点实验室,陕西西安710065

出　　处：《红外技术》2019年第10期895-901,共7页Infrared Technology

基　　金：国家自然科学基金(11535014)

摘　　要：在TiO2薄膜基底上制作多碱光电阴极,发现多碱光电阴极制作工艺无法正常进行,多碱光电阴极的颜色为暗黑色,并且阴极灵敏度非常低,而正常的多碱光电阴极应为红褐色。其中TiO2薄膜基底利用原子层沉积(ALD)工艺制备在玻璃窗上,并且具有锐钛矿晶体结构。X射线衍射仪(XRD)分析发现,制作多碱阴极后的TiO2薄膜样品锐钛矿衍射峰基本消失,另外X射线光电子能谱(XPS)分析发现该TiO2薄膜样品不同深度均存在Na元素,由此表明是Na元素渗透到TiO2薄膜中,破坏了薄膜的晶体结构,并且导致多碱光电阴极灵敏度非常低。为此提出了一种在制作多碱光电阴极之前,在TiO2薄膜上利用ALD工艺制作一层Al2O3钝化膜的方法。经过实验验证,证实该方法可以有效避免Na元素渗透到TiO2薄膜,同时多碱光电阴极制作过程可正常进行,多碱光电阴极的颜色为红褐色,阴极灵敏度超过800μA/lm。这为将来深入研究采用TiO2薄膜作为多碱光电阴极的减反膜打下了基础。In this study,experiments involving the deposition of a multi alkali photocathode on a TiO2 film were conducted.However,the manufacturing process of photocathode deposition did not proceed smoothly during this experiment.Furthermore,the photocathode was black in color(whereas it should be rufous under normal conditions)and its sensitivity was very low.In this experiment,a TiO2 film with anatase structure was deposited on a glass window by the atomic layer deposition(ALD)method,and the film was subsequently analyzed.The analysis results of X-ray diffraction(XRD)indicated that the diffraction peak of the anatase almost disappeared.In addition,the analysis results of X-ray photoelectron spectra(XPS)indicated that Na permeated into the TiO2 film.These results prove that the crystal structure of the TiO2 film was destroyed by Na permeation,causing very low sensitivity of the photocathode.Thus,an Al2O3 passive film deposited by the ALD method is proposed to address the Na permeation problem.Another experiment,in which a multi alkali photocathode was deposited on the TiO2 film with an Al2O3passive film,proved that the Na permeation is effectively prevented by the Al2O3 passive film.Importantly,the manufacturing process of photocathode deposition proceeded smoothly during the second experiment,the color of the photocathode was rufous,and the sensitivity of the photocathode was higher than 800μA/lm.These experiments form the basis of research on employing TiO2 films as antireflection films of multi alkali photocathodes in the future.

关 键 词：多碱阴极 TiO2减反膜 原子层沉积 Na元素渗透 钝化膜 

分 类 号：O462.3[理学—电子物理学]