点衍射干涉仪系统误差标定算法研究

Research on System Error Calibration Algorithm ofPoint Diffraction InterferometerJIANG Zhangde ' GAO Fen ' LI Bing (1.State Key Laboratory for Manufacturing Systems Engineering，Xian Jiaotong University，Xian 710049；2.School ofMechanical Engineering，Xial Jiaotong University，Xian 710049)Abstract：In order to evaluate absolute accuracy of point difraction interferometer(PDI)，a system error calibration method based ontilting and rotation of test miror is used and calibration algorithm are discussed in detail.Calibration formulas are deduced and averified simulation is conducted.In the method，figure ero of spherical test miror are measured in N equal position around aninitial axis and a tilt axis.The rotationally asymmetric component of real figure about test mirror in each axis position Can becalculated through rotation method.As system ero in same coordinate are constant in two rotate measurements，subtract one froman other，al equation cal be acquired without system eror term.The rotationally symmetric component of real figure whichexpressed in Zemike rotationaly items can be evaluated in solving this diferential equation with least square.System eror Can beacquired through deprive real figure eror of test mirror from measement data.Th e simulation results shows that figure eror of testmiror and system eror which calculated through this algorithm are consistent with the simulation input values，diference of errorsarelessthan 0.03 nnland residual ero arelessthan 0.3 nlTl，it Can meetthe requirementofthe calibration accuracy。

Key words：Point difr action Figure eror Difr action wavefront Rotationaly symmetric Rotationally asymmetric0 前言随着空间技术、军事技术、光刻技术等的发展，国家自然科学基金(51275398)、国家科技重大专项(2011ZX04004-061)、国家 自然科学基金重点(909230o1)、高等学校学科创新引智计划(B12016)、教育部科学技术研究重大(311001)和长江学者和创新团队发展计划(IRT1033)资助项目。20130131收到初稿，20130527收到修改稿对大口径、高精度光学元件的需求激增，对光学元件提出了纳米甚至亚纳米的超精面形加工和检测需求l J。如作为下-代主流光刻技术的极紫外光刻中，为了同时实现大的曝光视惩高成像分辨率，其微缩投影光学系统多采用 4～6片非球面反射镜实现，实际检测精度要求达到方均根(Root.mean.square，RMS)0.1～0.2 am的水平LZ圳。传统的菲索型和泰曼格林型激光球面干涉仪的检测精度受所用标准镜头2013年 8月 蒋庄德等：点衍射干涉仪系统误差标定算法研究 55径不同将对标定算法精度产生影响，该部分工作将在后续研究中进-步探讨。本文的研究结果对点衍射干涉仪系统误差的标定具有重要的理论指导意义和实用参考价值。