Plasmonic lithography for fabricating nanoimprint masters with multi-scale patterns

Abstract

We successfully demonstrate the practical application of plasmonic lithography to fabricate nanoimprint masters. Using the properties of a non-propagating near-field, we achieve high-speed multi-scale patterning with different exposure time during the scanning. We modulate the width of the line patterns using a pulse light source with different duty cycles during the scanning of the probe. For practical application in plasmonic lithography, we apply a deep reactive ion etching process to transfer an arbitrary fluidic channel into a silicon substrate and fabricate a high-aspect-ratio imprint master. Subsequently, we carry out the imprint process to replicate the fluidic channel with an aspect ratio of 7.2. For pattern width below 100 nm, we adopt a three-layer structure of photoresist, hard layer, and polymer to record the near field and form a hard mask and transfer mask. Using the multilayer structure, we fabricate high-resolution nanoimprint masters in a silicon substrate with an aspect ratio greater than 1.