Surface-enhanced Raman scattering on multilayered nanodot arrays obtained using anodic porous alumina mask

The fabrication of 3D multilayered nanodot arrays composed of metal (Au) and dielectric material (Al2O3) using ordered anodic porous alumina as a mask for vacuum evaporation was demonstrated. The obtained ordered multilayered dot arrays produced the accumulated nanogaps with controlled sizes, which can effectively enhance the electric field of incident light. The obtained structures with multilayered nanodots could be applied to the substrate for surface-enhanced Raman scattering (SERS) measurement, and larger SERS signals were obtained at larger numbers of multilayers and smaller gap seizes, corresponding to the effective enhancement of the electric field of incident light.