Roll-to-roll nanoimprint lithography for patterning on a large-area substrate roll

In this paper, we present a process for direct nanoimprint lithography from one roll to another. The basic concept of roll-to-roll nanoimprint lithography (R2R-NIL) is illustrated and the possibility of pattern-transfer between two cylindrical, curved surfaces is evaluated. For the replication of nanopatterns to a large-area roll from a small-area roll, the R2R-NIL process has to be conducted in a step-and-repeat manner. We were finally able to fabricate nanopatterns on a substrate roll of 250-mm diameter and 366-mm width. There exist seams and stitches of more than 1-mm in width on the patterned area of the substrate roll. For such a large roll, pre- and post-processes, including spin-coating, are also required. Even so, R2R-NIL is expected to be an effective tool to fabricate large-area rolls that can be used for the production of nanopattemed films. (C) 2014 Elsevier B.V. All rights reserved.