摘要
光栅横向剪切干涉仪能够实现超高精度检测光学系统的波像差,是当前光刻镜头研发的重要组成内容之一。零级串扰和相移误差是影响光栅剪切干涉仪检测精度的两个主要因素,为此,提出了一种十三步光栅剪切干涉相位复原算法,在消除零级串扰的同时,还能够极大地降低对相移误差的苛刻要求。分析表明,当相移误差不大于25°时,相位复原误差小于0.01°(即2.8×10-5λ)。对于λ=193.386nm,相位复原误差小于0.005nm。因此,通过系统误差校正,光栅剪切干涉仪检测光刻镜头系统波像差的精度能够达到亚纳米级。
Lateral shearing interferometer can achieve ultra-high-precision measurement of the optical system aberration. It is currently an important component content of the projection lens development. Two main factors affecting lateral shearing interferometry measurement accuracy are 0th order effect and phase shift error. Therefore, a thirteen-step phase restoration algorithm in phase shearing interferometry is proposed. It can 0th zeroth order effect and greatly reduce the phase shifting error demanding. Analysis shows that when the phase shift error is not more than 25 the phase restoration error is less than 0. 01 （2. 8 × 10-3λ）. For λ= 193. 386 nm, wavefront restoration error is less than 0. 005 nm. Thus, by system error correction wavefront measurement of projection lens of phase shearing interferometer can achieve sub-nanometer accuracy.
出处
《中国激光》
EI
CAS
CSCD
北大核心
2014年第5期178-181,共4页
Chinese Journal of Lasers
基金
国家重大科技专项(2009ZX02005)
关键词
测量
横向剪切干涉仪
相移算法
相位复原
measurement
lateral shearing interferometer
phase shifting algorithm
phase shifting error
