CMOS-MEMS Tuned-Mass-Damper Based Physical Unclonable Function (PUF)

This work demonstrates for the first time physical unclonable function (PUF) based on CMOS-MEMS resonant tuned-mass-damper (TMD) mode-localized resonators. Particularly, expanding upon the TMD resonator concept introduced in [1], this study utilizes the inherent process variation in the TMD structure that causes the magnitude mismatch between the two coupled vibration modes to realize digital fingerprints using mechanical means. Due to mode localization, the vibration magnitudes of the coupled modes exhibit high sensitivity to the actual TMD dimension. For a total of 28 dies measured, each of which comprises 49 TMD devices/bits, a total of 1372 bits successfully passes rigorous National Institute of Standards and Technology (NIST) randomness tests. Furthermore, these PUFs exhibit the favorable inter-Hamming Distances (inter-HDs) histogram centered at μ = 0.4623 with a standard deviation σ = 0.0739, and entropy characteristics close to 1, representing robust randomness and uniqueness. This MEMS-based technique presents a fresh paradigm for PUF generation with applications in specialized domains.