Fabrication of plasmonic nanostructures with electron beam induced deposition

摘要

The work described in this thesis was shaped by the goal---coming up new approaches to fabricate plasmonic materials with electron beam induced deposition (EBID). One-step, bottom-up and direct-write are typical adjectives that are used to indicate the advantageous properties of this technique. These properties enable us to produce complex, three-dimensional materials even on non-flat substrates in a rapid fashion. However, to fabricate plasmonic materials with EBID one needs to overcome some difficulties and limitations. The major challenge to solve is the impurity issue of the deposited metallic structures. We circumvent the impurity problem by deposition of silica instead of a metal. Metallic nanostructures are obtained by subsequent conformal thin gold film coating. At the end of the coating process we obtain a core-shell type plasmonic structures.ududAdditionally with the local deposition feature of EBID we load the gap of plasmonic split-wire gold nanoantennas. The loading is established with silica deposition. The gap field of the nanoantennas are loaded with various amount of silica. The optical properties of the loaded antennas are investigated with CL spectroscopy. The results reveal that the gap loading shifts the antenna resonance towards longer wavelengths as a function of the amount of deposited silica.ududLight-matter interaction related studies beyond the classical limits of the optics (nanophotonics) is a broad field. Both fundamental and applied nanophotonics investigations require state-of-the-art nanostructures with various geometries and material properties to push the boundaries. The work in this thesis demonstrates that EBID is an attractive nanofabrication technique to produce nanostructures that are three-dimensional, tunable (active or passive), with different materials, on different types of surface.