Optical lithography—present and future challenges

Optical lithography has been an industrial workhorse for many decades. It has reached a wavelength of 193 nm, a Numerical Aperture (NA) of 0.93 but was facing difficulties to advance further until the debut of immersion lithography. This review deals with the limit of dry and immersion lithography systems, their present and future challenges to reach these very limits. A discussion of defects in immersion lithography, the status of immersion lithography, polarized illumination, high-index materials, solid-immersion mask, double exposure and double patterning is included. To cite this article: B.J. Lin, C. R. Physique 7 (2006).