Ultrafast Laser Assembly of Metasurfaces with Large Scale Fabrication Capabilities

Project Information

METASCALE

Grant agreement ID: 101068089

DOI

10.3030/101068089

Project closed

EC signature date 20 July 2022

Start date 1 September 2023

End date 31 August 2025

Funded under

• Marie Skłodowska-Curie Actions (MSCA)

Total cost

No data

EU contribution

€ 165 312,96

Coordinated by

AGENCIA ESTATAL CONSEJO SUPERIOR DE INVESTIGACIONES CIENTIFICAS
Spain

Periodic Reporting for period 1 - METASCALE (Ultrafast Laser Assembly of Metasurfaces with Large Scale Fabrication Capabilities)

Reporting period: 2023-09-01 to 2025-08-31

Summary of the context and overall objectives of the project

The METASCALE project was launched to address an important challenge in modern optics: how to create advanced materials that can control light precisely, but in a way that is scalable, affordable, and environmentally friendly.

These materials, called metasurfaces, are extremely thin layers that can shape and manipulate light in ways that traditional optical components cannot. They have great potential for applications in imaging, communications, and sensing, but their use has been limited by the lack of simple and cost-effective manufacturing methods.

METASCALE set out to overcome this limitation by developing new laser- and soft-lithographt based hybrid fabrication techniques that allow metasurfaces to be produced directly on different materials, without the need for complex cleanroom processes. The project brought together expertise from materials science, ultrafast optics, and computational physics, and chemistry to create a new generation of fabrication tools for both research and industrial applications.

The work was organised around four main objectives:

Objective 1: Design new metasurface structures and develop fabrication plans using ultrafast laser processing and nanoimprint lithography.

Objective 2: Produce and characterise the materials needed for these structures, such as thin films and multilayer stacks, ensuring they meet the required optical and structural properties.

Objective 3: Understand how different fabrication parameters affect the quality and performance of the resulting metasurfaces.

Objective 4: Integrate all findings by producing large-area prototypes and testing their optical performance, scalability, and reproducibility.

Together, these steps created a clear pathway from concept to prototype, showing that reliable and sustainable metasurface production is possible using laser-based approaches.

In a broader sense, METASCALE contributes directly to Europe’s goals for sustainable and digital innovation. The project supports the development of cleaner, faster, and more flexible manufacturing technologies and helps strengthen Europe’s leadership in advanced materials and photonics. By showing that cutting-edge science can go hand in hand with environmental responsibility and industrial needs, METASCALE offers a strong example of innovation with real impact.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

The METASCALE project successfully pioneered and validated a suite of advanced, industry-compatible nanofabrication techniques for the scalable production of metasurfaces. These methods were designed to be large-area, cost-effective, and environmentally sustainable, while maintaining exceptional optical performance.

Throughout the project, we designed, fabricated, and tested a wide range metasurface prototypes using state-of-the-art scalable nanopatterning techniques such as direct laser writing,laser interference patterning, soft lithography, and innovative combinations of soft lithography with laser processing.

Key scientific and technological achievements include:

1. Demonstration of pulsed-laser-deposited bismuth thin films as a novel plasmonic buliding blocks, enabling the creation of gap-plasmon metasurfaces and structural color microprints with remarkable optical tunability.

2. Fabrication of plasmonic metagratings with extreme diffraction efficiencies, achieved through direct laser interference melting and solidification of metallic films on hybrid dielectric/metal substrates.

3. Realization of laser-induced periodic surface structures (LIPSS) on soft polymer materials, demonstrating excellent replication fidelity and robustness for functional wetting with potential for passive radiative cooling.

4. Development of a thermally stable, cost-efficient nanofabrication route for producing active phase-change metasurfaces capable of dynamic optical modulation across large areas.

METASCALE represented a highly interdisciplinary project, bridging fundamental research and industrial innovation. It opened new avenues towards low cost, and industry compatible optical devices, including reconfigurable photonic components, color printing, and smart surface technologies.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

The METASCALE project has made significant progress in pushing the boundaries of scalable fabrication of nanophotonic devices. By combining innovative materials, laser-based manufacturing, and nanoimprint lithography, the project demonstrated new ways to design and produce functional optical surfaces that are both scalable and environmentally-friendly.

One of the main achievements of METASCALE is the successful demonstration of unconventional nanofabrication techniques that go well beyond traditional cleanroom-based lithographic approaches. These methods allow for precise, large-area fabrication of nanostructures without relying on costly intensive processes. In particular, the following key additions to the state of the art were identified:

1. The discovery of plasmonic-like properties of bismuth thin films fabricated via pulsed laser deposition, which could provide a plasmonic alternative to scarce noble metals such as gold or silver.

2. The development of scalable fabrication routine to produce high-performance plasmonic metagratings in a single step, based on melting and solidification dynamics of metallic films on dielectric substrates

3. The demonstration of silicon laser-induced periodic surface structures (LIPSS) replicated on soft polymers, achieving highly uniform and controllable nanoscale patterns over centimeter squared areas. These surfaces exhibited excellent replication fidelity and mechanical robustness, maintaining their structural integrity even under repeated mechanical stress and environmental exposure. The resulting textures enabled tunable surface functionalities, particularly in controlling wettability and light–heat interactions, opening promising pathways for applications such as customised wetting properties or passive radiative cooling.

4. A thermally stable and cost-efficient nanofabrication route was developed for the production of active phase-change metasurfaces capable of dynamic optical modulation and chirality tuning over large areas. This development marks a significant step towards large scale fabrication of phase change material based metasurfaces, which to date have been fabricated using cost inneficient cleanroom processes.

Together, these advances establish a new generation of fabrication tools and material platforms for metasurface engineering. In summary, METASCALE has opened new technological possibilities for scalable, cost-effective, and eco-friendly metasurface fabrication which could be exploited by academic and industrial partners. Therefore, its results not only advance the scientific state of the art but also lay the groundwork for future industrial innovation in photonics and nanotechnology.

Examples of large-scale metasurface architectures developed during the implementation of METASCALE