Physical Unclonable Anticounterfeiting Electrodes Enabled by Spontaneously Formed Plasmonic Core–Shell Nanoparticles for Traceable Electronics

Counterfeit electronics are a growing problem for the electronic information industry worldwide, so developing unbreakable security tags is crucial to ensure the trustworthiness and traceability of electronics. Traditional anticounterfeiting and trace solutions rely on reproducible deterministic processes and additional labels, which can still be copied or faked by counterfeiters. Herein, physical unclonable functions enabled by spontaneously formed plasmonic core–shell nanoparticles on electrodes are proposed to ensure label‐free traceable electronics, giving a practical solution to fight against counterfeit electronics. Random hemispherical core–shell nanoparticles are intentionally introduced on the metal electrode of different semiconductors (Si, GaAs, and GaN) from Ni/Au bilayer heterofilms by rapid thermal annealing, which can be integrated with electronics seamlessly, with no negative effect on electrical properties. The position, size, and shape of nanoparticles are random and uncontrollable; the corresponding scattering patterns, intensity, and spectra can work as nanofingerprints of the electrode, proving multidimensional unclonable labels with large encoding capacity suitable for electrodes smaller than several micrometers. It can be further combined with machine vision and artificial intelligence to identify and track electronics automatically and efficiently. The anticounterfeiting electrodes also show good thermal robustness and mechanical stability, opening up a prospect for practical anticounterfeiting of electronics. Plasmonic core–shell nanoparticles are produced on electrodes by the rapid thermal annealing of bilayer nanofilms, providing a CMOS process compatible approach to produce a physical unclonable plasmonic anticounterfeiting label. The proposed unclonable anticounterfeiting electrodes show multidimensional encoding capacity together with good thermal robustness and mechanical stability, opening up a new prospect for label‐free trustworthiness and traceability of electronics.