Large-area nanostructured substrates for surface enhanced Raman spectroscopy

We demonstrate substantial enhancement of Raman transitions of organic molecules by nanostructured gold-coated substrates at the excitation wavelength of 785 nm and experimentally study the factors that influence the enhancement. The substrates are fabricated by using a robust and cost-effective nanopatterning technique that allows us to create high-density gold- or silver-coated nanopillars simultaneously on the whole surface of a standard silicon wafer.