US Patent 7618250 - Nanoimprint lithography optical alignment

http://www.freepatentsonline.com/7618250.html

This patent from ASML Netherlands B.V. teaches diffraction gratings used to align nanoimprint
lithography and enable multilayer patterning. Claim 1 reads:

1. An imprint lithography apparatus comprising:

a template holder configured to hold an imprint template, a substrate table, and an optical encoder, the optical encoder having a radiation output, a first diffraction grating, and a detector, the radiation output arranged to illuminate a second diffraction grating and the detector positioned to detect radiation diffracted by the first and second diffraction gratings to provide an alignment signal.

US Patent 7491661 - Immersion lithography including nanoparticle suspension topcoat

http://www.freepatentsonline.com/7491661.html

Higher resolution lithography is necessary to continue Moore's Law of increasing transistor density. One method to achieve such enhanced resolution is immersion lithography which uses a liquid medium to increase the index of refraction . This patent from ASML Netherlands B.V. teaches using a nanoparticle-based top layer to avoid internal reflection in immersion lithography systems. Claim 1 reads:

1. A device manufacturing method, comprising:

projecting a patterned beam of radiation through a liquid onto a resist provided on a substrate, wherein a topcoat layer is provided between the resist and the liquid, the topcoat comprising a suspension of nano-particles.