157 nm lithography is the most promising candidate for the post-193 nm lithography at the sub-70 nm technology node of semiconductor devices. In order to realize sub-70 nm resolution using 157 nm lithography, the critical components such as F2 laser, optics, photomasks, and resists have been studied extensively [Bloomstein et al., J. Vac. Sci. Techol. B 15, 2112 (1997); Rothschild et al., J. Photopolymer Sci. Technol. 13, 369 (2000); Rothschild et al. (unpublished); Itani and Wakamiya, Microelectron. Eng. 61–62, 49 (2002)]. Moreover, for improving the numerical aperture (NA) of the projection lens and thus the resolution capability at 157 nm, liquid immersion interference lithography at 157 nm has been studied and has obtained a minimum resolution of less than 70 nm lines and spaces [Switkes, Bloomstein, and Rothschild, Appl. Phys. Lett. 77, 3149 (2000); Switkes and Rothschild, J. Vac. Sci. Technol. B 19, 2353 (2001)]. In this article we will report on the feasibility study of a high NA (0.85 NA) projecti...