Tailored Optical Functionality by Combining Electron‐Beam and Focused Gold‐Ion Beam Lithography for Solid and Inverse Coupled Plasmonic Nanostructures

Abstract

Plasmonics is a field uniquely driven by advances in micro‐ and nanofabrication. Many design ideas pose significant challenges in their experimental realization and test the limits of modern fabrication techniques. Here, the combination of electron‐beam and gold ion‐beam lithography is introduced as an alternative and highly versatile route for the fabrication of complex and high fidelity plasmonic nanostructures. The capability of this strategy is demonstrated on a selection of planar as well as 3D nanostructures. Large area and extremely accurate structures are presented with little to no defects and errors. These structures exhibit exceptional quality in shape fidelity and alignment precision. The combination of the two techniques makes full use of their complementary capabilities for the realization of complex plasmonic structures with superior optical properties and functionalities as well as ultra‐distinct spectral features which will find wide application in plasmonics, nanooptics, metasurfaces, plasmonic sensing, and similar areas.

Hexagonal Plasmonic Arrays for High-Throughput Multicolor Single-Molecule Studies

“…The most promising approach to reduce the complexity of the lithography process is the combination of an etch-resistant positive-tone resist and reactive-ion etching (RIE) with chlorine-based etchants . In addition, emerging technologies like ion beam lithography (IBL) could also facilitate the fabrication of high-density HCP-AiB arrays . Enabling the fabrication of HCP-AiBs with a single lithography step would make HCP-AiBs as cost-effective as many other lithography-based nanophotonic platforms.…”

Focused Ion Beam Processing for 3D Chiral Photonics Nanostructures

“…Complex chiral plasmonic systems based on Ga nanostructures can be created by the interplay between the beam parameters and host media (the precursor) with a low molecular weight, leading to chiral plasmonic structures. Indeed, new research is currently under development for FIB source technology, investigating new kinds of alloy sources [ 155 ], even noble metals source like gold [ 156 ], always considered as the prime choice in plasmonic. Complex plasmonic structures with superior optical properties and functionalities can be realized with these innovative sources.…”

“…Finally, to the aim of a broad application gamut, the target of large area scalability is needed; a possible strategy could be the integration of a laser interferometer stage [ 39 , 156 ].…”

Understanding the impact of heavy ions and tailoring the optical properties of large-area monolayer WS2 using focused ion beam

“…Focused ion beam (FIB) milling is a powerful lithographic technique with nanometre resolution 1 and distinct advantages, especially when samples can potentially be damaged by wet chemicals that are required in electron-beam or photo-lithography processes. FIB lithography is often employed as the all-dry nanofabrication method for plasmonic [2][3][4] , photonic 5,6 and microfluidic 7 devices, in applications such as sensors, photodetectors, and light emitters [8][9][10][11][12] . Alongside these applications, recently FIB has shown great potential in surface modification and defect engineering in two-dimensional materials, especially in the transition metal dichalcogenides (TMDCs) family, with the aim to tailor their optical and electrical properties [12][13][14][15][16][17][18][19] .…”