Fabrication of Sub-Lithography-Limited Structures via Nanomasking Technique for Plasmonic Enhancement Applications

Fabrication of sub-10 nm features is advantageous for continued improvement of plasmonic enhancement applications. This letter demonstrates a technique, called nanomasking, which can fabricate nanostructures and gaps below the resolution limit of the lithography technique used in the process: nanogaps that are less than 10 nm in width, and nanostructures with 15 nm widths. This method improves upon existing techniques for creating metallic features at this scale, and it is also scalable for mass production. Unique structures that can be fabricated with this technique have been optically investigated to provide evidence as to their potential plasmonic applications.