Design And Fabrication Of Reconfigurable Physical Unclonable Function Based On Domain Wall Motion Driven By Spin-Orbit Torque

The rise of the Internet of Things has promoted the advancement of information technology and the development of smart mobile devices.A large amount of sensitive information is spread on smart platforms,posing a major security risk to personal privacy and information.Traditional hardware encryption methods rely on digital keys stored in nonvolatile memory,which are vulnerable to physical attacks such as side-channel attacks,and there is a risk of key leakage.The application of a protection circuit greatly increases hardware costs.Therefore,the lightweight Physical Unclonable Function(PUF)as an emerging hardware information security technology has attracted widespread attention and research.However,most researched silicon-based PUFs may have certain defects in terms of stability and safety.Therefore,the development of a PUF with high safety and stability based on new technology is an important current demand.At present,spintronic devices appear in people's field of vision with advantages such as non-volatility,low power consumption,compatibility with CMOS technology,and high endurance,and have received a lot of research and applications in the fields of memory and logic devices.This article explores the application of the stochastic properties of spin-orbit torque(SOT)induced domain walls motion in the field of PUF.Based on the perpendicularly magnetized Ta/CoFeB/MgO/Ta heterojunction structure,two device arrays of different sizes were designed and fabricated using micro-nano fabrication technology.Two kinds of reconfigurable PUF are realized by extracting the device to device variations of domain wall motion that induced by the inevitable errors in the manufacturing process and the cycle to cycle variations of stochastic domain wall motion caused by environmental thermal fluctuations,respectively.The results show that both PUFs have good uniqueness and reliability,the nonlinear behavior of domain wall and the reconfigurability greatly improve the security performance.This work applies spintronic devices to the field of information security,which retains the unique advantages of spintronic devices and improves the performance of PUF.