@inproceedings{abf1884c361d4e778772931b2d38a328,
title = "Design of chirped fly's eye uniformizer for ArF lithography illumiantion system",
abstract = "Fly's eye uniformizer is the key part of ArF lithography illumination system, whose main function is to illuminate the reticle uniformly. Due to the periodic structure of regular fly's eye uniformizer and the high coherence of the ArF laser, the output intensity distribution is modulated with equidistant sharp intensity peaks (interference speckle pattern) which disturbed the uniformity on the reticle. In this paper, we design a chirped fly's eye uniformizer which consists of chirped fly's eye and a condenser for illumination system in ArF lithography system. The chirped fly's eye consists of individually shaped micro-lenses defined by a parametric description which can be derived completely from analytical functions. The micro-lenses with different thicknesses in the chirped fly's eye have a function of delaying the optical path which reducing the laser coherence and speckle pattern on the reticle. Detailed design process of the chirped fly's eye uniformizer for numerical aperture (NA) 0.75 lithography illumination system is presented. Light intensity distribution on reticle produced by regular and chirped fly's eye uniformizer are analyzed and compared by the method of wave optics, and the results show that chirped can restrain sharp intensity peaks efficiently. Furthermore, the chirped fly's eye uniformizer has been traced in LightTools software under conventional and annual illumination modes, and the non-uniformity of the non-scan and scan direction on the reticle reached 0.75\% and 1.24\% respectively. The simulation results show that the chirped fly's eye uniformizer can provide high illumination uniformity and reduce the speckle pattern efficiently without additional elements.",
keywords = "ArF lithography system, Chirped fly's eye uniformizer, Illumination system, Optical design, Speckle pattern",
author = "Lei Xiao and Yanqiu Li and Lidong Wei",
note = "Publisher Copyright: {\textcopyright} 2014 SPIE.; International Symposium on Optoelectronic Technology and Application 2014 - Advanced Display Technology; and Nonimaging Optics: Efficient Design for Illumination and Solar Concentration, IPTA 2014 ; Conference date: 13-05-2014 Through 15-05-2014",
year = "2014",
doi = "10.1117/12.2072433",
language = "English",
series = "Proceedings of SPIE - The International Society for Optical Engineering",
publisher = "SPIE",
editor = "Roland Winston and Yongtian Wang and Yi Luo and Byoungho Lee and Yong Bi and Ting-Chung Poon",
booktitle = "International Symposium on Optoelectronic Technology and Application 2014",
address = "United States",
}