摘要
首先针对可变入射角的反射法消光椭偏测试系统,讨论其计算公式和求解思路,建立了全局目标优化函数,提出一种网格优化算法,即计算中可半智能跟踪最优解的方法。利用新算法解决了求解中的多峰问题,从而可以高精度计算薄膜的折射率与厚度。开发了相关软件,处理进口椭偏仪测量的消光参数,获得了大入射角条件下SiO2 薄膜的折射率和厚度,并与其它方法的计算结果进行对比分析,发现此方法计算结果可以达到更高的精度,有利于指导微米到纳米级复杂结构和成分的薄膜光波导的性能分析。最后通过对较小入射角实测数据的分析,指出了传统理论模型在光斑干涉效应及衍射效应方面的不足。
The calculation formula of reflector ellipsometers with variable incidence angles and its solution were disussed firstly. One kind of Overall optimization algorithm was proposed,so that the multi-peak problem in solutions was resolved,and the refractive index and thickness of thin films can be calculated in high precision. Then by this new algorithm, the refractive index and thickness of SiO 2 film have been calculated easily from the extinction parameters measured under large incidence angles. The results show more accuracy than that of other solutions, that benefits for studying μm^nm film optical waveguides with complex structrues and compositions. At last some reasons for the bad results under small incident angles was presented.
出处
《激光与红外》
CAS
CSCD
北大核心
2005年第3期214-216,共3页
Laser & Infrared
基金
福建省青年科技人才创新项目资金提供资助 (No.2001J024)。
关键词
椭圆偏振法
折射率和膜厚
全局优化算法
ellipsometer
refractive index and film thickness
overall optimization algorithm
