Nanomeshes at Liquid Interfaces: From Free‐Standing Hole Arrays toward Metal–Insulator–Metal Architectures

The superior optical properties of metamaterials often rely on hierarchical structures in the sub‐wavelength regime comprising stacks of individually patterned layers. For the fabrication of metamaterials in the visible regime, specific top‐down lithographic methods have been developed. These techniques, however, have several inherent drawbacks such the lack of scalability and low production speeds. Here, a simple and modular approach for the construction of multilayer metal–insulator–metal structures based on the transfer of metal nanohole arrays via liquid interfaces is demonstrated. Gold nanohole arrays are used as model systems that are prepared via nanosphere lithography on a zinc oxide sacrificial layer. Exploiting an interface mediated method, the prepared nanohole arrays are subsequently transferred onto arbitrary hydrophilic or hydrophobic substrates without compromising the high quality of the nanomeshes. Two approaches to stack such nanostructured layers with nanometer precision in a rapid way are demonstrated. Finally, the high mechanical stability of only 100 nm thick gold nanohole arrays allows for the preparation of free‐standing nanomeshes in the order of several hundreds of square‐micrometers.