Further investigations on traps stabilities in random telegraph signal noise and the application to a novel concept physical unclonable function (PUF) with robust reliabilities

Abstract

A novel physical unclonable function (PUF) that based on random telegraph signal noise (RTN) is proposed and studied in this work. Firstly, systematical experiments have been done in ultra-scaled devices with various gate stack structures. It is found for the first time that strong correlations between trap time constants and thermal activation energies universally exist in all devices, no matter for hole traps or for electron traps, in high-k dielectrics or in SiO2. More importantly, time constants are stress free and quite stable under electrical stressing. Then, with proposed transient RTN approaches and algorithms, RTN related traps can be detected in a short time and directly utilized in PUF designs. The hamming distance (HD) of intra-PUF and inter-PUF is experimentally characterized, showing excellent endurance properties with no less than 1E6 ID reading cycles.