Sub-15 nm nanoimprint molds and pattern transfer

This work addresses the challenges in fabricating sub-10 nm sized features, dense sub-15 nm half-pitch arbitrary-pattern nanoimprint molds, as well as pattern transfer of the molds using nanoimprint. The molds were fabricated using an optimized electron-beam lithography process with hydrogen silsesquioxane HSQ resist. Two different mold-processing routes were investigated: 1 HSQ patterns on top of a silicon substrate were directly used for nanoimprint and 2 the HSQ patterns on the mold were transferred into the underlying silicon substrate to increase the aspect ratio of the patterns prior to imprint. After the nanoimprint, lift-off was carried out to demonstrate that the pattern could be transferred into functional materials. The difference between the two mold-processing routes is discussed. The results show excellent resolution transfer throughout the process flow to create sub-15 nm half-pitch patterns in functional materials. © 2009 American Vacuum Society. DOI: 10.1116/1.3264670