Tamper-Responsive Physical Unclonable Functions via Graphene-Interlayered Block Copolymer Random Structures.

Abstract

Microscopically engineered materials inherently harbor unique structural signatures arising from the stochastic fabrication. Physical unclonable functions (PUFs) exploit structural randomness to generate unique cryptographic responses, establishing hardware-based security. However, conventional PUF architectures rely on static configurations to guarantee authentication reproducibility, and the intrinsic rigidity permits unauthorized reverse-engineering without detectable traces. A tamper-responsive physical unclonable function (TR-PUF) platform is presented, integrating a high-entropy source with a reactive two-dimensional material interlayer to actively defend cryptographic keys. The entropy source relies on fingerprint-like nanopatterns derived from thermodynamic fluctuations during block copolymer self-assembly, while a reduced graphene oxide interlayer leverages out-of-plane chemical and mechanical sensitivity enabling device responsiveness to external intrusions. Systematic characterization confirms robust fundamental cryptographic performance, with near-ideal uniqueness and uniformity. Also, the tamper-responsive capability is demonstrated across three representative intrusion scenarios, where simulated high-resolution probing, chemical, or mechanical attempts to access the internal architecture trigger spontaneous and irreversible key invalidation via localized degradation. Furthermore, broad applicability is validated through rigorous environmental survivability assessment under low Earth orbit simulated conditions, alongside seamless integration across diverse form factors. The autonomous hardware protection framework opens possibilities for securing electronic components across next-generation hardware architectures in strategic fields like space missions and military applications.