Nanostructure transfer using cyclic olefin copolymer templates fabricated by thermal nanoimprint lithography

Abstract

The authors demonstrate the application of cyclic olefin copolymer (COC) films as secondary nanoimprint templates for transferring sub-100 nm nanostructures. Featureless COC films were first patterned by a thermal nanoimprint process using silicon molds with gratings of various periods from 140 to 420 nm. Morphology of COC gratings imprinted at different processing parameters was characterized by scanning electron microscopy and atomic force microscopy and the grating transfer fidelity was systematically investigated. The nanoimprinted COC substrates were then used as secondary templates in an ultraviolet (UV)-cured nanoimprint lithography process to transfer the grating patterns onto UV-curable epoxy. The authors also demonstrate the application of using these nanoimprinted COC templates to transfer metallic nanostructures onto fiber facets. With good mechanical strength, high transparency to UV light, easy fabrication, and excellent chemical compatibility, COC is a promising material that can be used in low-cost secondary templates for large-volume nanoimprint-based manufacturing of nanostructured devices.