Surface and interference coenhanced Raman scattering of graphene.

We propose a novel surface and interference coenhanced Raman scattering technique to dramatically enhance the Raman signal intensity of graphene by using a specifically designed substrate of Si capped with surface-active metal and oxide double layers (SMO). The total enhancement ratio can reach the order of 10(3) compared with the original Si substrate. Combining the visibility of graphene on the SMO substrate, we demonstrate that the tiny structure change and surface structure of graphene can be easily detected. This technique makes Raman spectroscopy a more powerful tool in the field of ultrasensitive characterization of graphene, isolated carbon nanotubes, and other film-like materials.