Litho-aware and low power design of a secure current-based physically unclonable function

Abstract

Physically Unclonable Functions (PUFs) are lightweight cryptographic primitives for generating unique signatures from complex manufacturing variations. In this work, we present a current-based PUF designed using a generalized lithographic simulation framework for improving inter-die and inter-wafer uniqueness. The sensitivity of the circuit to manufacturing variations is enhanced by placing the gate structures at pitches closer to forbidden zone, where the sensitivity of Critical Dimension (CD) to the pitch variations is very high. Simulation results show that the litho-aware current based PUF has improved inter- and intra-distance over the conventional current-based PUF. The litho-aware PUF consumes about 0.034 pico joules of energy per response bit, which is substantially better than delay-based PUF implementations.