A Portable Dynamic Switching Model for Perpendicular Magnetic Tunnel Junctions Considering Both Thermal and Process Variations

In this paper, we develop a portable dynamic switching model for perpendicular magnetic tunnel junctions (MTJs) considering both thermal fluctuation and process variations. The model uses macro-spin approximations where the free layer (FL) of MTJ is assumed to be in a single-domain structure. The model can generate dynamic switching transience curves at different current densities and simulate the switching successful rates for the given pulse lengths at different current densities. We also use the model to study the impact of temperature and device process variations on the switching performance, such as switching time variations. It is shown that the temperature effect is not significant when the switching current is relatively larger, and hence the spin current effect is strong enough to overtake the temperature effect. As for the process variations, it is shown that the FL thickness has a more significant effect on the switching time than the size of the FL does.

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