Manufacturing a surface enhanced Raman spectroscopy (SERS) active structure includes exposing a substrate to produce an exposure pattern then etching the substrate based on the exposure pattern to produce a plurality of nanostructure cores having a plurality of sides extending from the substrate. Adjacent nanostructure cores are separated by core gaps. SERS active material is deposited onto the plurality of nanostructure cores producing a structure having gaps suitable for use in a SERS process.