基于白光干涉的光学薄膜物理厚度测量方法  

Thickness Measurement of Thin Film Based on White-Light Spectral Interferometry

作　　者：薛晖[1] 沈伟东[1] 顾培夫[1] 罗震岳[1] 刘旭[1] 章岳光[1] 

机构地区：[1]浙江大学现代光学仪器国家重点实验室,浙江杭州310027

出　　处：《光学学报》2009年第7期1877-1880,共4页Acta Optica Sinica

基　　金：国家自然科学基金(60708013;60778025)资助课题

摘　　要：设计了一套利用白光干涉理论测量薄膜厚度的系统,主要包括迈克耳孙白光干涉系统和光纤光谱仪。对干涉信号进行频域分析,结合拟合测试与理论能量曲线的方法并选择合适的目标函数,进一步精确反演得到待测薄膜样品的物理厚度,使用上述方法对多组不同厚度的薄膜样品进行计算,并对结果进行了详细的精度及误差分析。将本实验装置测试所得到的数据与传统的光度法相比较,结果表明使用该测试方法测量光学薄膜物理厚度的误差可以小于1 nm。与传统的光度法和椭偏法相比,提供了一种测量光学薄膜厚度的较为简单、快速的解决方案,同时保证了较高的精度。A new method of measuring thickness of optical thin film with dispersive white-light spectral interferometry is proposed. By analyzing the recorded interference spectrum in the frequency domain and fitting the recorded channel spectrum to the theoretical value, the thin-film thickness can be determined. The thicknesses of several different thin film samples are calculated and the results show that this method can reach high precision with the error less than 1 nm. The new method can provide a simple and fast solution in calculating thickness of optical thin films, compared with traditional spectrophotometric and ellipsometric method, while still maintaining high accuracy.

关 键 词：白光干涉 测量薄膜物理厚度 等效厚度 频域分析 

分 类 号：O436.1[机械工程—光学工程]