Rapid Electrohydrodynamic Lithography Using Low‐Viscosity Polymers

Abstract

This study explores a number of low-viscosity glass-forming polymers for their suitability as high-speed materials in electrohydrodynamic (EHD) lithography. The use of low-viscosity polymer films significantly reduces the patterning time (to below 10 s) compared to earlier approaches, without compromising the high fidelity of the replicated structures. The rapid pace of this process requires a method to monitor the completion of EHD pattern formation. To this end, the leakage current across the device is monitored and the sigmoidal shape of the current curve is correlated with the various stages of EHD pattern formation.

Numerical studies of electrically induced pattern formation by coupling liquid dielectrophoresis and two‐phase flow

“…Electrically induced patterning process has been explored as a novel structuring approach for fabrication of various micro-or nano-devices, and demonstrated to be capable of generating periodically regular gratings, pillars or grids in micrometer or sub-micrometer scales onto a dielectric polymer film [1][2][3]. The implementation of this patterning process typically starts up with development and maintaining of a fluidic and dielectric polymer film on a substrate, and then involves application of an electrical potential across a template and the polymer-coated substrate as a pair of the electrodes which are placed in parallel and separated with an air gap, finally followed by a solidification usually through photo-or thermo-curing of the patterned fluidic polymer.…”

Hierarchical Electrohydrodynamic Structures for Surface‐Enhanced Raman Scattering

“…The wedge geometry causes predominantly a variation in τ , affecting λ only very little. [ 17 ] This enables the visualisation of different stages of the instability on a single sample. Initially, the fi lm develops low-amplitude undulations ( Mechanism of the HEHD structure formation process.…”

Electrohydrodynamic Patterning of Functional Materials

“…EHD lithography has previously been used to fabricate patterns in a variety of polymers using both featureless and topographically structured masks [38,39]. Furthermore, EHD lithography allows to pattern most of the amorphous and semi-crystalline polymers [39]. Positional control of the generated morphologies can be adjusted by varying a number of experimental parameters, such as the initial film thickness, inter-electrode spacing, E p -strength, surface tension and lateral periodicity of the master electrode.…”

“…when a topographically patterned top electrode is used, the EHD patterning process yields a high fidelity replication of the patterns imposed by the master top electrode. EHD lithography has previously been used to fabricate patterns in a variety of polymers using both featureless and topographically structured masks [38,39]. Furthermore, EHD lithography allows to pattern most of the amorphous and semi-crystalline polymers [39].…”