摘要
在极值法光学膜厚监控中,使用多少监控片且何时更换(即监控片更换策略)在一定程度上是该膜系镀制成功与否的一个关键因素。分析了在反射式极值法光学监控中监控片更换策略的数值模型。根据大量的实验得到的工艺参数,在不同过正控制量下首次进行了监控片更换策略优化的沉积仿真模拟。结果表明:在多腔结构膜系的沉积过程中存在着"假性"极值,容易导致某些膜层厚度的严重误差。不同的过正控制量对光学监控效果会产生明显地影响;所给定的过正控制量存在着最佳的监控片更换策略;合适的变过正控制量可进一步改善薄膜的光学性能。
Optical monitoring is the control of choice for high precision optical manufactures. To some extent, the strategy of changing witness chips is one of the key factors to determine the optical performance of coatings. The numeric model on turning point monitoring based on the optimization of the strategy of changing witness chips is analysed elaborately, and the deposition simulation on different extreme overshoot has been successfully demonstrated. The results show that during the deposition of the films with the construction of coupling layers, pseudo extremums will appear, leading to severe thickness errors of some layers. Different extreme overshoot have distinct effect on the results of optical monitoring. Given an overshoot, the optimal strategy of changing witness chips can be attained. In addition, the optical performance of the coatings can be improved to a large extent by setting appropriate variable overshoots.
出处
《光学技术》
EI
CAS
CSCD
北大核心
2005年第2期266-268,271,共4页
Optical Technique
关键词
光学监控
过正控制量
沉积仿真
光学薄膜
optical monitoring
overshoot
deposition simulation
optical films
