Nanoimprint lithography (NIL) allows the patterning of large areas within a few seconds using a nanostructured stamp. First, single functional NIM layers were fabricated on silicon substrates using a two-layer lift-off process. Next, these single layers were peeled off from the substrate using a UV-curable hybrid polymer Ormocomp as "glue". Repeating this process several times and stacking the single layers on top of each other leads to 3D NIM.

The stacking process can be performed on quartz, glass and also flexible substrates and takes only a few minutes. It is applicable to a very wide and general class of nanostructured thin films as well as optical metamaterials.

The group has demonstrated NIMs with a resonance frequency in the infrared. Further experiments will follow to achieve 3D NIMs within the visible regime.

Additional information can be found in the journal Nanotechnology.