The diagnosis and control of the polarization aberrations is one of the main concerns in a hyper numerical aperture (NA) lithography system. Waveplates are basic and indispensable optical components in the polarimetric diagnosis tools for the immersion lithography system. The retardance of a birefringent waveplate is highly sensitive to the incident angle of the light, which makes the conventional waveplate not suitable to be applied in the polarimetric diagnosis for the immersion lithography system with a hyper NA. In this paper, we propose a method for the optimal design of a wideview- angle waveplate by combining two positive waveplates made from magnesium fluoride (MgF₂) and two negative waveplates made from sapphire using the simulated annealing algorithm. Theoretical derivations and numerical simulations are performed and the results demonstrate that the maximum variation in the retardance of the optimally designed wide-view-angle waveplate is less than ± 0.35° for a wide-view-angle range of ± 20°.

Date Published: 15 March 2016
PDF: 9 pages
Proc. SPIE 9780, Optical Microlithography XXIX, 97801M (15 March 2016); doi: 10.1117/12.2219139

Published in SPIE Proceedings Vol. 9780:
Optical Microlithography XXIX
Andreas Erdmann; Jongwook Kye, Editor(s)