Near-zero surface pressure assembly of rectangular lattices of microgels at fluid interfaces for colloidal lithography

TL;DR

This paper introduces a novel method for assembling microgels into rectangular lattices at fluid interfaces with near-zero surface pressure, enabling their use as lithography masks for nanowire fabrication.

Contribution

The study demonstrates a new approach to self-assemble microgels into ordered lattices at fluid interfaces using capillary interactions and steric effects, advancing colloidal lithography techniques.

Findings

Rectangular microgel lattices can be assembled at near-zero surface pressure.

The assembled lattices serve as effective masks for nanowire patterning.

The method is applicable to a broad range of microgel particles.

Abstract

Understanding and engineering the self-assembly of soft colloidal particles (microgels) at liquid-liquid interfaces is broadening their use in colloidal lithography. Here, we present a new route to assemble rectangular lattices of microgels at near zero surface pressure relying on the balance between attractive quadrupolar capillary interactions and steric repulsion among the particles at water/oil interfaces. These self-assembled rectangular lattices are obtained for a broad range of particles and, after deposition, can be used as lithography masks to obtain regular arrays of vertically aligned nanowires via wet and dry etching processes.