摘要
基于严格的光学成像矢量衍射理论,以4倍缩小倍率的成像系统和x线偏振光照明为例,得到经光瞳滤波器调制的大数值孔径光学系统焦区横向场表达式.通过详细研究非对称三区复振幅型光瞳滤波器的内外环归一化半径、各环相位分布和第一层透过率t对y方向分辨率增益比Gty,斯特尔比Sy和第一旁瓣与主瓣相对强度Iry的影响.设计了一种非对称三区相位型光瞳滤波器,实现Gty=0.8345,Sy=0.4087,Iry=0.4923,使得y方向分辨率比没有加光瞳滤波器时提高了将近20%.
Based on the rigorous vector imaging theory of an optical system, taking the optical imaging system with amplification of 1/4 and the x linearly polarized illumination as an example, the transverse electric field expression in focal region was obtained when the x linearly polarized light passes through an optical system with high numerical aperture modulated by a pupil filter. A new kind of dissymmetrical three-zone phase pupil filter was designed by studying in detail such parameters of the three-zone complex pupil filter as the influences of the normalized radiuses of the inner and outer zones, the phase distribution in each zone,and the transmittance t of the first zone on the superresolution gain ratio Gty ,the Strehl ratio Sy and the relative intensity ratio of the sidelobe to that of the central lobe Iry in y direction,respectively. According to the simulation results,Gty =0. 834 5,Sy=0. 4087,and Iry =0. 492 3 are achieved,and the designed phase pupil filter can improve the resolution in transverse y direction by nearly 20% in contrast to that in the optical imaging system without pupil filter. This new kind of three-zone dissymmetrical phase pupil filter with superresolution in a single transverse direction can be effectively applied to the resolution enhancement technology （RET） in an advanced photolithography with the double exposure technique.
出处
《光子学报》
EI
CAS
CSCD
北大核心
2008年第11期2222-2226,共5页
Acta Photonica Sinica
基金
国家973基础研究发展计划(2005CB724304)
国家自然科学基金(60777045
60807007)
上海市科学技术委员会重点基础研究项目(07JC14056)
上海市教育发展基金会(2007CG61)
上海科技启明星基金(08QA14051)
上海高校选拔培养优秀青年教师科研专项基金(slg-07004)资助
