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arXiv · 1206.4148

Super-resolution Imaging by Evanescent Wave Coupling to Surface States on Effective Gain Media

Prateek Mehrotra·Chris A. Mack·Richard J. Blaikie
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Abstract

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 λ=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.

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Prateek Mehrotra, Chris A. Mack, Richard J. Blaikie. 2012-06-19. Super-resolution Imaging by Evanescent Wave Coupling to Surface States on Effective Gain Media. https://arxiv.org/abs/1206.4148

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