Adv. Mater. 23, 4422–4430 (2011)

Credit: © 2011 WILEY

There have been some impressive examples of photonic devices aimed at new platforms such as stretchable substrates. However, although larger-scale conventional devices such as light-emitting diodes have been widely demonstrated for such platforms, the fabrication of nanoscale structures has remained challenging. Hatice Altug and colleagues have now developed a deposition technique that is able to fabricate plasmonic structures on flexible substrates with nanoscale precision. Their approach is based on nanostencil lithography, where a stencil mask is placed on a substrate and the desired metallic structures are evaporated on the substrate through the holes in the mask. Removal of the mask exposes the desired structures. In the present case, a silicon nitride mask was used to deposit gold nanostructures on a stretchable polymer substrate, with a remarkable accuracy of 10 nm. The polymer sheets are very flexible and can, for example, be placed around the surface of an optical fibre. The rise in the use of plasmonic phenomena for applications such as molecular sensing suggests that this low-cost and high-throughput fabrication process could lead to devices for such uses.