基于波像差判据的同步相移显微干涉检焦方法  

Synchronous phase-shifting microscopic interference focal detection method based on wave aberration criteria

作　　者：胡乔伟 高志山[1] 袁群[1] 黄旭 孙一峰 王灵杰[2] 张建萍[2] HU Qiaowei;GAO Zhishan;YUAN Qun;HUANG Xu;SUN Yifeng;WANG Lingjie;ZHANG Jianping(School of Electronic and Optical Engineering,Nanjing University of Science and Technology,Nanjing 210094,China;Key Laboratory of Optical System Advanced Manufacturing Technology,Changchun Institute of Optics,Fine Mechanics and Physics,Chinese Academy of Sciences,Changchun 130033,China)

机构地区：[1]南京理工大学电子工程与光电技术学院,江苏南京210094 [2]中国科学院长春光学精密机械与物理研究所光学系统先进制造技术重点实验室,吉林长春130033

出　　处：《应用光学》2021年第4期703-708,共6页Journal of Applied Optics

基　　金：国家重点研发计划(2019YFB2005500);中国科学院光学系统先进制造技术重点实验室开放基金(KLOMT190201);江苏省六大人才高峰项目(RJFW-019)。

摘　　要：为了实时准确地将激光直写系统中经直写物镜聚焦的光斑定位于待加工元件表面,提出了一种基于波像差判据的同步相移显微干涉检焦方法,实现了对离焦量的实时检测与调整。在直写系统中引入检焦光路,与直写光路共享同一物镜,构建Linnik型同步相移显微干涉检焦系统,提取包含离焦量的波面相位信息;再从大数值孔径(NA)的物镜波像差数据中解析出离焦量的大小与方向。仿真结果验证了基于波像差判据的离焦计算方法的正确性,NA≥0.5时,离焦探测灵敏度可达4 nm,通过实验验证了同步相移显微干涉检焦方法的可行性,检焦精度可达10 nm以内,满足激光直写高精度的测量要求。In order to accurately locate the focused spot of the laser direct writing system on the surface of the element to be machined in real time,a synchronous phase-shifting microscopic interference focal detection method based on wave aberration criteria was proposed,which realized the real-time detection and adjustment of the defocusing amount.The focal detection optical path was introduced in the direct writing system,and shared the same objective lens with the direct writing optical path.The Linnik synchronous phase-shifting microscopic interference focal detection system was constructed to extract the wave surface phase information containing the defocusing amount.Then the magnitude and direction of defocusing amount was analyzed from the wave aberration data of objective lens with large numerical aperture(NA).The simulation results verify the correctness of defocusing calculation method based on wave aberration criteria,when NA≥0.5,the defocusing detection sensitivity can reach to 4 nm.The experimental results verify the feasibility of synchronous phaseshifting microscopic interference focal detection method,and the precision can reach within 10 nm,which can meet the high-precision measurement requirements of laser direct writing.

关 键 词：实时检测 同步相移 显微干涉 波像差 离焦量 

分 类 号：TN206[电子电信—物理电子学]