Enhanced non-volatile resistive switching performance through ion-assisted magnetron sputtering of TiN bottom electrodes

Abstract Emerging non-volatile memristor-based devices with resistive switching (RS) materials are being widely researched as promising contenders for the next generation of data storage and neuromorphic technologies. Titanium nitride (TiN x ) is a common industry-friendly electrode system for RS; however, the precise TiN x properties required for optimum RS performance is still lacking. Herein, using ion-assisted DC magnetron sputtering, we demonstrate the key importance not only of engineering the TiN x bottom electrodes to be dense, smooth, and conductive, but also understoichiometric in N. With these properties, RS in HfO 2 -based memristive devices is shown to be optimised for TiN 0.96 . These devices have switching voltages ≤ ±1 V with promising device-to-device uniformity, endurance, memory window of ~40, and multiple non-volatile intermediate conductance levels. This study highlights the importance of precise tuning of TiN x bottom electrodes to achieve robust performance of oxide resistive switching materials.