Compact Model of Conductive-Metal-Oxide/HfO_x Analog Filamentary ReRAM Devices

We pioneer a physics based compact model of analog filamentary conductive-metal-oxide (CMO)/HfO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</inf> ReRAM devices. Drawing from established physics-based models, we extend and customize them to explain the resistive switching mechanism in our analog ReRAM devices. Current transport in analog ReRAM devices involves carriers hopping through the localized defect states in the CMO layer, while in conventional filamentary ReRAM devices, it relies on ohmic and tunneling conduction. The model considers the ionic diffusion and drift currents as a function of the temperature dynamics and the electric field distribution. As the analog resistive switching arises from the redistribution of oxygen vacancies within a dome region in the proximity of the HfO<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">x</inf> filament, we establish the time-dependent analytical description of the oxygen vacancy concentration in each resistance state. The compact model is validated using quasi-static voltage sweep data, resulting in a strong agreement between model predictions and experimental results.