X-ray and Proton Radiation Effects on 40 nm CMOS Physically Unclonable Function Devices

Abstract

Total ionizing dose effects are investigated on a physically unclonable function (PUF) based on CMOS breakdown. Devices irradiated to 2.0 Mrad(SiO2) show less than 11% change in current ratio at 1.2 V. The read-out window of programmed PUFs decreases significantly at high dose proton irradiation, and then recovers back to the original value after annealing. The proton test results for the pFET selector, the unbroken nFET, and the broken nFET indicate that the threshold voltage shift of the pFET selector contributes mainly to the degradation of the PUF.