Scalable Photo-Responsive\nPhysical Unclonable Functions\nvia Particle Kinetics

The increasing menace of counterfeiting and information\ntheft underscores\nthe urgent need for security platforms compatible with both micro-\nand nanoelectronics. Existing methods for anticounterfeiting labeling\nand cryptographic systems rely on unclonable patterns derived from\nthe unpredictable variability of physical phenomena. However, these\napproaches impose limitations on the scalability of security components.\nHere we present a scalable platform for photoresponsive physically\nunclonable functions based on oxide particle kinetics in polymer solutions.\nThe stochastic agglomeration process occurring during the formation\nof polymer films with dispersed oxide particles yields random patterns,\nwith pixel sizes scalable from micro to nanoscales. We produce mechanically\nflexible and self-destructible optical unclonable function patterns\nutilizing oxide aggregates on a polymer film. Moreover, we establish\na strategy for generating electrical unclonable patterns on a conducting\npolymer film. This involves covering the polymer film with an aggregate\npattern mask, which serves as an ultraviolet-blocking layer for randomly\nexposing the film to ultraviolet ozone treatment. These unclonable\npatterns constitute robust and compact security systems, exhibiting\neffective resilience against machine-learning attacks (∼50%\nprediction error for training data sets of 1000). The developed scalable\nplatforms for physically unclonable functions provide a hardware solution\nfor robust cryptographic applications.