紫外薄膜光学常数的多层模型椭偏测量  

Measurement of Optical Constants for UV Coating Based on Multilayer Film Model by Spectroscopic Ellipsometry

作　　者：吴慧利[1] 唐义[1] 白廷柱[1] 蒋玉蓉[1] 蒋静[1] 

机构地区：[1]北京理工大学光电学院光电成像技术与系统教育部重点实验室,北京100081

出　　处：《光电工程》2015年第9期89-94,共6页Opto-Electronic Engineering

基　　金：国家973计划(2013CB329202);工业技术基础项目(J312012B002)资助

摘　　要：研究了基于光谱式椭偏仪精确测量紫外弱吸收薄膜光学常数的可靠方法。以Hf O2和Si O2薄膜为研究对象,用光谱式椭偏仪测量了薄膜的多角度椭偏参数,采用逐点优化法,建立了多层模型。利用Cauchy-Urbach模型进行数据拟合,获得了Hf O2和Si O2薄膜在200?900 nm波段的光学常数,并比较双层薄膜拟合结果和扫描电镜的测量结果,验证了获得的光学常数的准确性。结果表明,逐点优化法结合Cauchy-Urbach模型能够较好地描述弱吸收薄膜的结构,较为准确地得到薄膜的色散关系,可为紫外滤光片的后期制作奠定基础。A reliable and accurate method based on multilayer film model by spectroscopic ellipsometry is proposed to measure optical constants of UV weak absorption films. Take examples of HfO2 film and SiO2 film, multi-angle ellipsometry parameters Psi and Delta had been measured by spectroscopic ellipsometry to inverse optical constants of HfO2 and SiO2 film between 200 nm and 900 nm in Wavelength, which were fitted by point-by-point method using the Cauchy with urbach absorption model. Comparing the fitting result of ellipsometry and the test result of scanning electron microscopy （SEM）, we verified the accuracy of the optical constants of HfO2 and SiO2 film. The results show that the structure and optical constants of weak absorption coating can be better described by Cauchy with urbach absorption model using point-by-point method, and the results are important for the fabrication of UV filters.

关 键 词：薄膜光学 弱吸收薄膜 光学常数 光谱式椭偏仪 

分 类 号：O484.5[理学—固体物理]