A Strong Physical Unclonable Function With Virgin State Embedded Phase Change Memory

Physical unclonable functions (PUFs) have gained attention in recent years due to the increasing demand for secure, compact, and power-efficient electronic devices in the Internet of Things (IoT). PUFs can provide a unique physical fingerprint to each device, which is a valuable means of enhancing security through the generation of unique and volatile cryptographic keys with no need to store them in nonvolatile memory (NVM). A major concern regarding PUF solutions for low-cost authentication is achieving robustness, a large challenge-response pair (CRP) space, and high reliability against environmental variations at the same time. In this work, we present a PUF system based on embedded phase change memory (PCM) in the virgin state with an industry-standard one-transistor/one-resistor (1T1R) cell, exploiting the wide resistance distribution as an entropy source. The PUF system is validated based on extensive physics-based simulations of embedded PCM cells integrated with 90-nm technology, showing raw reliability in temperature comparable with state-of-the-art solutions which can be further improved using dedicated schemes for the selection of reliable CRPs.