A Multiphysical Field Dynamic Behavioral Model of Perpendicular STT-MTJ

The spin transfer tunnel magnetic tunnel junction (STT-MTJ) has been widely used in computers, memory, and other fields because of its nonvolatility, low power consumption, and high capacity for integration, attracting significant attention in recent years. Building an accurate and efficient magnetic tunnel junction (MTJ) behavior model is necessary to accurately describe the physical changes caused by variations in external excitation and guide the design and optimization of magnetic random access memory (MRAM). In this paper, we construct a multiphysical field dynamic behavior model of a perpendicular STT-MTJ, introducing temperature and frequency effects based on the Landau–Lifshitiz–Gilbert–Slinbczewski (LLGS) equation and a macro model. Compared with the LLGS model, our model simplifies the calculation of the tunneling current and shortens the simulation time by ~40%. Compared with the macro model, ours model can more accurately reflect the dynamic physical changes in magnetoresistance under a small signal and transient excitation. Simulation modeling and experimental comparison verify the temperature and frequency dependencies of the model. Our model provides guiding significance for the design, application, and research of MTJ devices’ electromagnetic compatibility characteristics.