Abstract

Recently, ArF immersion lithography has been considered as a promising method after ArF dry lithography by a factor of refractive index n of the liquid filled into the space between the bottom lens and wafer, in the case of 193-nm exposure tools, water (n = 1.44) has been found as the best liquid. We explore the NA?'s dependence of depth of focus (DOF) under 3/4 annular and 3/4 quasar illumination by resist imaging simulation. Line/space pairs of line-to-space ratios 1:1, 1:2, 1:4 on binary mask are considered. Finally, we explored the high NA's dependency of DOF and gave the explanation for the peak value of DOF through three-beam imaging process, MicroCruiser 2.0, Prolith version 8.0.2 and k_2 factor based on the Rayleigh equation.

© 2005 Chinese Optics Letters

Inorganic immersion fluids for ultrahigh numerical aperture 193 nm lithography

Jianming Zhou, Yongfa Fan, Anatoly Bourov, and Bruce W. Smith
Appl. Opt. 45(13) 3077-3082 (2006)

Air bubble-induced light-scattering effect on image quality in 193 nm immersion lithography

Yongfa Fan, Neal Lafferty, Anatoly Bourov, Lena Zavyalova, and Bruce W. Smith
Appl. Opt. 44(19) 3904-3911 (2005)

193nm Superlens Imaging Structure for 20nm Lithography Node

Zhong Shi, Vladimir Kochergin, and Fei Wang
Opt. Express 17(14) 11309-11314 (2009)

22-nm immersion interference lithography

T. M. Bloomstein, M. F. Marchant, S. Deneault, D. E. Hardy, and M. Rothschild
Opt. Express 14(14) 6434-6443 (2006)

Depth-of-focus (DoF) analysis of a 193nm superlens imaging structure

Zhong Shi, Vladimir Kochergin, and Fei Wang
Opt. Express 17(22) 20538-20545 (2009)