点衍射干涉仪波面参考源误差及公差分析

为了保留光纤点衍射干涉仪容易对准以及衍射光束易于控制的优点，同时又能实现大数值孔径（NA）光学系统的检测，设计了一种新型的波面参考源（WRS），它保留了光纤点衍射和微孔点衍射的优点，可满足大NA极紫外光刻物镜系统波像差检测的要求。本文在分析各种误差的基础上，搭建了WRS原理光路并对WRS的系统误差标定算法进行详细的研究，得到WRS标定时旋转平台的角度公差为0.5°，跳径时偏离系数为0.5%。这一新型WRS误差分析及标定对于实现高精度的检测具有十分重要的意义，最终为实现WRS系统误差标定提供理论基础。

Analysis on error and tolerance for the wavefront reference source of point diffraction interferometer

To keep the advantages of fiber point diffraction interferometer which is easy to align and control the diffracted light, we design a new wavefront reference source(WRS). WRS can keep the advantages of fiber point diffraction interferometer and pin-hole point diffraction interferometer, and it also can be used to test the wavefront aberration of larger NA optical system for Extreme Ultraviolet Lithography(EUVL). The analysis of error for this new WRS and calibration of the system error is very important for realizing a more accurate test of wavefront aberration. Based on the analysis of various errors, we study the calibration algorithm in detail, and obtain the tolerance of several WRS important components including that the angle tolerance of rotation stage is 0.5° and the deviation factor is 0.5% when rotation is away optical axis.