  Higher resolution demands for semiconductor lithography may be fulfilled by
higher numerical aperture (NA) systems. However, NAs more than the photoresist
refractive index (~1.7) cause surface confinement of the image. In this letter
we describe how evanescent wave coupling to effective gain medium surface
states beneath the imaging layer can counter this problem. At {\lambda}=193 nm
a layer of sapphire on SiO2 counters image decay by an effective-gain-medium
resonance phenomena allowing evanescent interferometric lithography to create
high aspect ratio structures at NAs of 1.85 (26-nm) and beyond.
