Optimization and characterization of Au cuboid nanostructures as a SERS device for sensing applications

Gold cuboid nanostructures with edge size in the range of 40–65 nm and inter-particle separation of 20 nm were fabricated by electron beam lithography. The aim of the present work is to investigate the effect of cuboid size on surface enhanced Raman scattering intensity and, thereby, to optimize the size of nanostructures in order to maximize signal enhancement. The electric field distribution of 4 × 4 array of Au cuboid nanostructures was numerically simulated by commercial software. A monolayer of Rhodamine-6G is deposited on the device using chemisorption technique, finding an enhancement factor ∼104, which candidates the cuboid nanostructures as a promising enhanced Raman substrate.

Figure optionsDownload as PowerPoint slideHighlights
► Reproducible cuboid structures with edge size in the range from 40 to 65 nm are fabricated by EBL.
► Metallic nanostructures were shown to be highly effective SERS substrates, EF: 104.
► Cuboid structures provide a novel strategy towards bio/chemical sensing capability.