Nanoscale Fabrication Techniques for Plasmonic Nanostructures

The fabrication of plasmonic nanostructures at the sub-10 nm scale underpins advances in sensing, photonic circuitry and metamaterials. Top-down approaches such as electron-beam lithography, focused ion beam milling and adhesion lithography offer precise control of feature dimensions and interparticle gaps but can be limited by throughput and scalability. Bottom-up methods, including nanosphere lithography and self-assembly, enable large-area patterning and cost-effective production yet typically depend on careful control of colloidal masks and etching conditions. Hybrid strategies combine the strengths of both paradigms: atomic layer deposition can define uniform dielectric spacers in wafer-scale electron-beam patterns, while direct superplastic nanoimprinting enables one-step fabrication of metallic nanowire arrays with sub-10 nm features. Recent progress has also been achieved in anisotropic etching of colloidal masks to create three-dimensional plasmonic geometries. Together, these techniques support finely tuned localized surface plasmon resonances, high-quality factor metasurfaces and robust substrates for surface-enhanced spectroscopy. The convergence of throughput, precision and materials versatility is now driving practical devices for biosensing, on-chip optical interconnects and energy harvesting.

Research from Nature Portfolio

One-step superplastic nanoimprinting below melting temperatures has emerged as a versatile route to high-aspect-ratio metal nanorod arrays. By applying controlled pressure and heat below the bulk metal’s melting point, crystalline features as small as 8 nm are formed in a single imprinting step, yielding substrates with strong surface-enhanced Raman scattering signals and potential for mass production under ambient conditions. A separate adhesion lithography method exploits self-assembled monolayers to weaken the bond between sequential metal films and generate asymmetric nanogap electrodes with aspect ratios exceeding 100,000. This ambient-condition process uses minimal equipment and rapid pattern transfer to create sub-15 nm gaps for optoelectronic devices. These foundational techniques illustrate how simple chemomechanical strategies can overcome the throughput and scalability limitations of conventional electron-beam lithography while maintaining nanometre precision.

Nanoscale Fabrication Techniques for Plasmonic Nanostructures publication trend

The graph below shows the total number of articles in nanoscale fabrication techniques for plasmonic nanostructures across all publications each year (not limited to Nature Index journals).

Technical terms

Electron-beam lithography (EBL): A top-down technique using a focused electron beam to write high-resolution patterns in resist for nanoscale device fabrication.

Atomic layer deposition (ALD): A vapour-phase method that deposits materials in atomic-scale, layer-by-layer fashion, enabling precise thickness control.

Nanosphere lithography (NSL): A bottom-up approach that uses self-assembled colloidal spheres as masks to create periodic nanostructures upon deposition and etching.

Superplastic nanoimprinting (SPNI): A method in which crystalline metals are deformed below their melting points to replicate nanoscale features in a single imprinting step.

Localized surface plasmon resonance (LSPR): The collective oscillation of conduction electrons in metallic nanostructures excited by light, leading to strong near-field enhancement.

Adhesion lithography: A rapid fabrication technique using self-assembled monolayers to modulate adhesion between sequential metal layers and create nanogap electrodes.

References

1. Controlling Vertical Asymmetry of Nanocrystals Through Anisotropic Etching‐Assisted Nanosphere Lithography. Small Structures (2023).
2. Wafer-scale nanofabrication of sub-5 nm gaps in plasmonic metasurfaces. Nanophotonics (2024).
3. Sub-10 nm fabrication: methods and applications. International Journal of Extreme Manufacturing (2021).
4. Sub-15-nm patterning of asymmetric metal electrodes and devices by adhesion lithography. Nature Communications (2014).
5. One-step fabrication of crystalline metal nanostructures by direct nanoimprinting below melting temperatures. Nature Communications (2017).
6. High-Throughput Fabrication of Triangular Nanogap Arrays for Surface-Enhanced Raman Spectroscopy. ACS Nano (2022).