A method of fabricating a surface enhanced Raman scattering (SERS) substrate. In one embodiment, the method has the steps of simultaneously evaporating a metal at a first evaporation rate and a polymer at a second evaporation rate different from the first evaporation rate, to form a nanocomposite of the metal and the polymer, depositing the nanocomposite onto a substrate, and applying an etching process to the deposited nanocomposite on the substrate to remove the polymer material, thereby forming an SERS substrate.