Off-line inspection method of microlens array for illumination homogenization in DUV lithography machine
Illumination uniformity is one of the key specifications of lithography illumination system because of its strong influence on the critical dimension(CD)uniformity in optical lithography.Refractive microlens array(MLA)has been extensively adopted in lithography system to achieve highly homogeneous illumination field with less light loss relative to diffractive element.Off-line homogenization inspection of the MLA provides important data for entire system integration.It is still a challenge work to investigate the optical performance for such high-end MLA with large clear aperture and high sensitivity to the incident light parameters.In order to address these issues,subaperture stitching method has been proposed to be applied and studied in this work.The feasibility of this method has been verified by theoretical simulation of a diffracting homogenizer.In the experiment,a corresponding optical setup is constructed,and a crossed-cylindrical single-plate MLA has been tested.The experimental results are consistent with the simulation ones.It could be concluded that subaperture stitching method is a powerful method to evaluate the homogeneous performance of MLA.
optical lithography illumination homogenization microlens array off-line inspection of MLA subaperture stitching
Zhang Fang Zhu Jing Yang Baoxi Huang Lihua Hu Xiaobang Xiao Yanfen Huang Huijie
Shanghai Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Shanghai 201800,China;Un Shanghai Institute of Optics and Fine Mechanics,Chinese Academy of Sciences,Shanghai 201800,China
国际会议
2013 International Conference on Optical Instrument and Technology (OIT’2013)(2013年光学仪器与技术国际会议)
北京
英文
1-9
2013-11-17（万方平台首次上网日期，不代表论文的发表时间）