A Physics-Based Dynamic Model of HfO₂-Based Ferroelectric Tunnel Junctions With Dual-Insulator Structure

A physics-based compact model for the metal–ferroelectric–insulator–metal (MFIM) tunneling junctions, compatible with metal–ferroelectric–metal (MFM) structures, is developed to cover their essential dynamic features. The dual-insulator introduces a complex shape of tunneling barriers, which also exhibits a dependence on the history of ferroelectric (FE) polarization. Voltage control of the ferroelectric tunnel junction (FTJ) is formulated using the dynamic nucleation-limited switching theory. Key operational voltages are analyzed, especially for those with zero internal fields. The tunneling transport is analytically formulated, covering the dual-insulator barriers and the above special bias points based on the Wentzel–Kramers–Brillouin (WKB) approximations. The developed model, validated against both experimental data and TCAD simulations, demonstrates key features of the developed model including quasi-static and dynamic state transitions, historical dependence, and time-modulated multiple states. This model provides a unified framework for the simulation and optimization of both MFIM and MFM tunnel junctions, facilitating their potential applications in nonvolatile memory (NVM) and neuromorphic computing.