TiO2薄膜的宽光谱特性椭偏法研究

摘要

为了获得TiO2薄膜的光学常数，采用德国SENTECH生产的SE850宽光谱反射式光谱型椭偏仪，测量和分析了用光控自动真空镀膜机沉积在K9玻璃上的单层TiO2薄膜，得到了TiO2薄膜在300nm～2500nm宽谱上的光学常数曲线和薄膜厚度。根据TiO2的薄膜特性及成膜特点，考虑了表面粗糙层和界面层对薄膜性能的影响，建模时采用Cauchy指数模型和Tauc-Lorentz模型，对建立的各种模型测量得到的数据进行了分析和比较。结果表明，模型“基底／Tauc-Lorentz模型／表面粗糙层”可以得到最小的均方差为0．5544，得到的TiO2薄膜的厚度的测量值与TFCalc软件的计算值最接近。该研究结果对TiO2薄膜多层膜膜系设计和制备有参考价值。%In order to obtain optical constants of TiO 2 thin film, single-layer TiO2 film deposited on K9 glass with an optical automatic vacuum coating machine was measured and analyzed with a SE 850 broadband ellipsometer produced by SENTECH , Germany, and the optical constant curve and thickness of TiO 2 thin film in 300nm~2500nm spectrum were obtained .Based on the film characteristics and film forming characteristics of TiO 2 film, taking the influence of the intermix layer and rough surface layer into account , models were set up with Cauchy index model and Tauc-Lorentz model and the measurement data were analyzed and compared.The smallest mean square error of 0.5544 was obtained with a so called model of “substrate/Tauc-Lorentz model/rough surface layer”.The measured TiO 2 thickness was closest to calculation value of TFCalc software .The results have certain reference value for the design and preparation of TiO 2 thin multilayer film.