薄膜光学常数和厚度的测量方法及技术研究  

Research on Measurement Methods and Techniques for Optical Constants and Thickness of Thin Films

作　　者：章大鹏 陈妍 徐中辉[1] ZHANG Dapeng;CHEN Yan;XU Zhonghui(School of Information Engineering,Jiangxi University of Science and Technology,Ganzhou Jiangxi 341000,China;School of Electrical Engineering and Automation,Jiangxi University of Science and Technology,Ganzhou Jiangxi 341000,China)

机构地区：[1]江西理工大学信息工程学院,江西赣州341000 [2]江西理工大学电气工程与自动化工程学院,江西赣州341000

出　　处：《佳木斯大学学报（自然科学版）》2024年第10期176-180,共5页Journal of Jiamusi University：Natural Science Edition

基　　金：江西省科技厅项目(20224BAB201023);江西理工大学优秀人才计划项目(3203304666);赣州市科技创新人才计划项目(赣市科发[2019]60-43)。

摘　　要：详细介绍了基于光谱拟合反演薄膜参数的方法,得到了简化后的薄膜-基底光学系统的透射率公式,借助Cauchy模型,建立了光谱拟合评价函数。采用改进型遗传算法得到Si薄膜在500~800nm波长范围内的光学常数和厚度,结果表明,薄膜折射率和厚度的计算精度较高,平均误差仅为0.1%和0.2%,而消光系数的误差也能控制在10%左右。该方法具有操作简单、计算速度快、结果精确等特点。This article provides a detailed introduction to the method of inversion of thin film parameters based on spectral fitting,obtaining a simplified transmittance formula for the thin film substrate optical system.With the help of the Cauchy model,a spectral fitting evaluation function is established.The simplified transmittance formula of the thin film substrate optical system is obtained,and a spectral fitting evaluation function is established using the Cauchy model.The improved genetic algorithm was used to obtain the optical constants and thickness of Si thin films in the wavelength range of 500~800 nm.The results showed that the calculation accuracy of the refractive index and thickness of the films was high,with average errors of only 0.1%and 0.2%,and the error of extinction coefficient could also be controlled around 10%.This method has the characteristics of simple operation,fast calculation speed,and accurate results.

关 键 词：光谱拟合 Cauchy模型 遗传算法 数字滤波 

分 类 号：O484.4[理学—固体物理]