Physically Unclonable Functions with Voltage-Controlled Magnetic Tunnel Junctions

We demonstrated for the first time physically unclonable functions (PUFs) based on voltage-controlled magnetic tunnel junctions (VC-MTJs). The proposed PUF completely extracts the intrinsic variation of magnetization switching in the VC-MTJ as a random bit string without a short pulse, which is required in the spin-transfer torque (STT) MTJ and spin-orbit torque (SOT) MTJ-based PUF. Moreover, it can be initialized by a bias voltage without an external magnetic field. Using 40 MTJs fabricated in the same design, we evaluated the PUF fundamental parameters: uniqueness, reliability, and uniformity as 57.5%, 87.1%, and 45.0%, respectively.