Near-field distribution in light-coupling masks for contact lithography

We discuss the potential and limitations of Light-coupling masks for high-r esolution subwavelength optical lithography. Using a three-dimensional full y vectorial numerical approach based on Green's tensor technique, the near- field distribution of the electric field in the photoresist is calculated. We study the dependence of the illuminating Light and the angle of incidenc e on polarization. Furthermore, we investigate the replication of structure s of various sizes and separations. It is predicted that the formation of f eatures in the 60 nm range is possible using light with a 248 nm wavelength . However, with decreasing separation among the features, crosstalk limits the ultimate resolution. (C) 1999 American Vacuum Society. [S0734-211X(99)0 4606-5].