Microfabricated SERS-arrays with sharp-edged metallic nanostructures

By means of e-beam lithography, vacuum evaporation and ion-beam etching we have developed fabrication routes for the realisation of very small and sharp-edged metallic nanostructures which can be used as substrates for surface enhanced Raman spectroscopy (SERS). The metallic nanostructures are made from gold, are periodically arranged with a pitch of 250 nm and have sharp edges with corner radii of less than 20 nm. These structures show uniform SERS-signals across the whole field size of 200 × 200 μm², and a dependency of the SERS signal intensity and of the signal-to-noise ratio on the pattern geometry. Thus the microfabricated SERS-substrates are suitable for practical applications.