Effect of stamp design on residual layer thickness and contact pressure in UV nanoimprint lithography

Abstract

Pattern density is an important factor in UV nanoimprint stamp design. Various pattern densities may affect the thickness of the residual layer and its uniformity. This work investigated the effect of pattern density as well as other stamp parameters, including stamp material, stamp thickness and cavity height, on residual layer thickness (RLT), contact pressure, and imprint quality. Two kinds of stamps were designed for simulation, one with detached uniform lines and the other with adjacent non-uniform lines. Results show that areas near the edges of the imprint field in all stamps are the first to achieve high contact pressure. The study observed that long imprint time enables a reduction of RLT after a stable period, particularly obvious with high density. For a long-term imprint of patterns with various densities, flowing behaviour of the residual resist was revealed. These conclusions are beneficial for making guidelines for stamp design in UV nanoimprint lithography.

Flexible and transparent electrodes imprinted from metal nanostructures: morphology and opto-electronic performance

“…Defects in the conformal stamp-substrate contact due to edge imperfections and reduced contact pressure around the channel edges aggravate the effect. 37 Figure 2E is a transmission electron micrograph of a plasmatreated line on a silicon substrate. The change of the crosssectional profile during plasma sintering was minor.…”

“…Defects in the conformal stamp-substrate contact due to edge imperfections and reduced contact pressure around the channel edges aggravate the effect. 37 …”

Multilevel nanoimprint lithography with a binary mould for plasmonic colour printing

“…Although we have demonstrated that a variable imprint depth provides an additional degree of freedom in creating plasmonic colouration, in many applications this can be undesirable. Several approaches have been proposed to reduce the global variation of imprint depth such as increasing the applied pressure, 42 increasing the imprinting time, 31,43 introducing additional microcavities or protrusions in proximity to the original design 33 and utilising a cavity-equalized mould. 36 To address this issue, we propose the addition of a novel mesh-like microcavity architecture to the multi-density mould to facilitate resist ow.…”

The implementation of thermal and UV nanoimprint lithography for selective area epitaxy

“…While pressure variations due to pattern density can be remedied by modeling the stamp design [38,39], another non-negligible effect came from the nanoimprinting tool. Any roughness present on the printer plates resulted in defects in the imprinted regions.…”