Physically Unclonable Surfaces via Dewetting of Polymer Thin Films

Area of Science:

• Materials Science
• Nanotechnology
• Surface Chemistry

Background:

• Growing demand for encoded surfaces with multiple security layers.
• Need for adaptable fabrication methods combining stochastic and deterministic approaches.

Purpose of the Study:

• To present dewetting instabilities in nanoscopic polymer films as a physically unclonable function (PUF).
• To demonstrate the fabrication of unclonable surfaces using stochastic processes adaptable to deterministic fabrication.

Main Methods:

• Utilizing thermal annealing-induced dewetting of poly(2-vinyl pyridine) (P2VP) on polystyrene-grafted substrates.
• Creating randomly positioned functional features via dewetting instabilities.
• Fabricating plasmonic PUFs using electrostatic interactions with gold nanoparticles.

Main Results:

• Demonstrated unclonable surfaces with features separated at microscopic length scales.
• Achieved optical authentication via visible light reflection.
• Developed plasmonic PUFs with surface-enhanced Raman scattering and taggants for molecular vibration-based security.

Conclusions:

• Dewetting instabilities in polymer films offer a robust platform for fabricating physically unclonable functions (PUFs).
• The developed hybrid security labels are resolvable through both stochastic and deterministic pathways.
• The method's adaptability, simplicity, and stability make it suitable for diverse encoding applications.