A Unified Memristor Compact Model for RRAM, FERAM/FTJ, and MRAM

This article presents a unified compact model, UMEM, tailored to memristor devices, such as resistive random access memory (RRAM), ferroelectric (FE) capacitor, ferroelectric RAM (FERAM), FE tunnel junction (FTJ), and magnetic RAM (MRAM). A unified differential equation formulation is presented to describe the switching dynamics and resistance in memristors: 1) a physical switching model for RRAM has been developed to accurately represent diverse shapes of RRAM I–V curves and inherently constrain filament length; 2) the nucleation-limited-switching (NLS) model of FEs is revisited and the multigrain-aware dynamic theory is developed, which does not require space/grain integration. The new FE model is over ten times more computationally efficient than the NLS theory; and 3) the MRAM model, which is based on the Landau–Lifshitz–Gilbert (LLG) equation, is adapted for integration into this unified framework, providing solutions for asymmetric switching and state pinning. The model is verified with experimental data and is robust in SPICE simulation. The proposed model is applicable to both DC and transient simulation and complies with the compact model coalition (CMC) Verilog-A model pythonic rule enforcer (VAMPyRE).