0.67‐μm ² /bitcell two‐transistor leakage‐based physically unclonable function with native bit‐instability of 0.89% at 65 nm

Abstract

A compact and robust physically unclonable function (PUF) for secure key generation is proposed. With the help of a cross-coupled amplifier, the leakage-current mismatch between the two transistors was digitised to produce a unique chip identification. The measurement results show that the proposed PUF has the best-in-class randomness and uniqueness, as well as the following features: (i) an ultra-small PUF cell with a minimum feature size of 159 F 2 , being the lowest reported to date in CMOS, (ii) a low native BER (bit-instability) of 0.16% (0.89%) was measured at the golden condition, and (iii) an autocorrelation of 0.007 at 95% confidence was achieved.