Modeling of In-Plane Magnetic Tunnel Junction for Mixed Mode Simulations

The incredible potentials of spin transfer torque (STT) magnetic random access memories (MRAMs) give them an edge over other memory technologies. Most of the projections show them as universal memory in the future; however, their evolution is still in a rudimentary stage. Attaining a high density in STT MRAMs is imperative to keep pace with the scaling scenario in field effect transistors (FETs) and hence competitive with future processors. A vertical or a two terminal select device can be a possible solution to achieve the high-density problem. A suitable platform is required for simulating a hybrid magnetic tunnel junction (MTJ)/FET circuit before an actual fabrication is done. However, most simulation tools do not have the capability to model hybrid MTJ/FET devices. Also, the SPICE compatible models for such devices and other novel structures like vertical FET are not available. This paper addresses the above-mentioned concerns and proposes a model for MTJ (coded in C++) and a simulation platform for hybrid MTJ/FET device-circuit co-design with physics-based models. The proposed model is validated using mixed mode simulations.