Solid-State Dewetting and Optical Properties of Metallic Thin Films

Solid-state dewetting describes the spontaneous retraction of a continuous metallic thin film into discrete particles or islands when subjected to thermal annealing. Driven by minimisation of surface and interface energies, this process is governed by surface diffusion, substrate wettability and film thickness. Morphological evolution ranges from isolated nanoparticles to networked patterns, with the final architecture strongly influenced by substrate chemistry, pre-patterning and alloy composition. Optical properties emerge from the interaction of light with these nanostructures, most notably through localised surface plasmon resonances (LSPR), in which conduction electrons oscillate collectively at metal–dielectric interfaces. Tunability of LSPR peak position, intensity and bandwidth is achieved by controlling particle size, shape, interparticle spacing and composition. Such control underpins advances in sensing, photonic devices, plasmonic catalysis and flexible optoelectronics. Recent progress has focused on in situ observation of dewetting pathways, the role of multimetallic layers in tailoring plasmonic modes, and integration of atomically thin interlayers to stabilise ultrathin films. This confluence of dewetting dynamics and plasmonic functionality continues to expand the utility of metallic thin films across fields as diverse as surface-enhanced spectroscopy, photovoltaics and thermal management.

Research from Nature Portfolio

Recent studies have systematically probed the link between dewetting temperature and surface-enhanced Raman scattering, demonstrating that silver nano-island arrays produced via controlled annealing yield reproducible hotspots and correlate quantitative nucleation theory with electromagnetic simulations. Other work has exploited sequential solid-state dewetting of bi-layer and tri-layer films to assemble multimetallic nanoparticles with finely tuned LSPR bands spanning the ultraviolet to visible range, revealing that sublimation of one component can sculpt composition and resonance strength. A complementary approach has patterned aluminium nanobowl arrays prior to gold deposition, using topographical guidance during dewetting to produce high-density, ordered gold nanoparticle arrays with plasmonic responses tunable from the visible into the near-infrared for sensor applications.

Solid-State Dewetting and Optical Properties of Metallic Thin Films publication trend

The graph below shows the total number of articles in solid-state dewetting and optical properties of metallic thin films across all publications each year (not limited to Nature Index journals).

Technical terms

Solid-state dewetting: Thermal process by which a continuous thin film retracts into discrete islands to minimise interfacial energy.

Localised surface plasmon resonance (LSPR): Collective oscillation of conduction electrons in metallic nanoparticles excited by incident light, producing sharp optical absorption or scattering peaks.

Surface diffusion: Movement of atoms or molecules along a surface driven by gradients in chemical potential or curvature.

Mullins’ coefficient: Parameter describing the rate of hole growth in dewetting films as a function of material properties and temperature.

Volmer–Weber growth model: Thin-film deposition regime where three-dimensional islands nucleate directly on a substrate due to weak film–substrate interactions.

References

1. A study on the correlation between the dewetting temperature of Ag film and SERS intensity. Scientific Reports (2017).
2. Assembly of gold nanoparticles into aluminum nanobowl array. Scientific Reports (2017).
3. Fabrication of transferable ultrathin Au films with eminent thermal stability via a nanocrystalline MoS2 interlayer. Materials Today Nano (2024).
4. Influence of Au alloying on solid state dewetting kinetics and texture evolution of Ag and Ni thin films. Surfaces and Interfaces (2024).
5. Effects of annealing temperature and duration on the morphological and optical evolution of self-assembled Pt nanostructures on c-plane sapphire. PLOS ONE (2017).