Graphene covered metallic nanostructures provide a unique platform for plasmonic enhanced graphene devices. Recently, single layer graphene was transferred and studied onto arrays of metallic nanoparticles, fabricated by lithographic methods.We integrate graphene with plasmonic Si substrates. We prepare arrays of nanopillars on the surface of Si (black Si) by femtosecond laser irradiation in water. Laser nanostructuring of Si provides a simple, maskless, large area, cost effective method for the fabrication of plasmonic substrates. Coating the structured Si surface by a thin metallic layer results in the spontaneous formation of metallic smooth metallic film. The whole process is scalable and not inherently size limited. Single layers of graphene are prepared by chemical vapor deposition on transition metal catalytic substrates (Cu foil) and transferred on the plasmonic Si substrates by a PMMA scaffolding method. The properties of black Si supported graphene are studied by scanning electron microscopy and optical reflectance spectroscopy. We probe the graphene layer for its plasmonic enhanced Raman spectral signal via Raman spectroscopy. Optical reflectance spectra demonstrate the coupling between localized surface plasmons and graphene. The Raman signal of graphene on black Si, coated with metallic nanoparticles, is enhanced by orders of magnitude, compared with all other reference substrates employed, i.e., (a) graphene on black Si without metallic nanoparticles and (b) graphene on flat Si with or without metallic coating. This result paves the way for future realworld applications of large area hybrid nanomaterials.
D.G. Kotsifaki, N. Kelaidis, S.A. Giamini, J. Marquez Velasco, A. Dimoulas, G. Kordas, M. Kandyla, ​2016 Spring : Symposium O | EMRS

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