How to print plasmonic 3D nanostructures with an electron beam

Plasmonic nanoparticles exhibit distinctive optical properties and are therefore increasingly integrated into a variety of commercial products and technologies, spanning from photovoltaics over chemical/physical sensors toward quantum devices. Since material, geometry, size and arrangement of the nanostructures determine their optical performance, controlling these aspects in every detail allows to tailor their plasmonic response according to the targeted application. However, achieving this reliably for complex 3D nanoarchitectures still remains a challenge. Herein, we present the application of Focused Electron Beam Induced Deposition (FEBID), for the controlled fabrication of plasmonically active, well-defined 3D nanostructures with predictable optical properties.[1] As part of our study,
planar gold nanowires and 3D nanotips of various geometries were fabricated via FEBID and their plasmonic activity subsequently characterized through STEM-EELS mapping measurements. Our experimental findings were further supported by corresponding plasmon simulations, showing excellent agreement. This approach enables on-demand spectral tuning of the plasmonic response through upfront modeling and design of tailored 3D nanostructures, thus opening doors to new plasmonic applications in 3D space.