5 July 2000 Realization of very small aberration projection lenses
Author Affiliations +
To implement low-k1 lithography, it is most fundamental to reduce aberrations of projection lenses for the exposure tools, not only in the optical design, but also in the manufacturing process. This paper will reveal a new lens manufacturing concept utilizing Zernike circle polynomials to overcome such difficulties. Sets of Zernike coefficients are used to describe the surface accuracy of each element or wavefront aberrations of assembled lens, and each coefficient itself becomes the target of element polishing or lens tuning. Adopting these targets is the most effective way to control actual optical performance and result in a great improvement of the projection lenses. We present some topics of our new manufacturing process and the performance progress up to our latest KeF stepper, FPA-3000EX6.
© (2000) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Toshiyuki Yoshihara, Toshiyuki Yoshihara, Ryo Koizumi, Ryo Koizumi, Kazuhiro Takahashi, Kazuhiro Takahashi, Shigeyuki Suda, Shigeyuki Suda, Akiyoshi Suzuki, Akiyoshi Suzuki, } "Realization of very small aberration projection lenses", Proc. SPIE 4000, Optical Microlithography XIII, (5 July 2000); doi: 10.1117/12.389045; https://doi.org/10.1117/12.389045


Back to Top