An Efficient Approach Based on Tuned Nanoionics to Maximize Memory Characteristics in Ag‐Based Devices

Abstract

AbstractThis study demonstrates a systematic approach to modulate the oxygen vacancy concentration within a Ag/HfO2/Pt based resistive switching device and control the volatile and nonvolatile switching through tuned nanoionics. A synergistic effect of oxygen vacancy formation and metal ion migration generates several shades of storage behavior in the same matrices. An optimized vacancy engineering methodology is investigated to control the anatomy of the filament formation after pre‐forming process from 100 pA to 10 µA. More specifically, the impact of pre‐forming driven oxygen vacancy path is identified, which successfully produces volatile threshold switching and nonvolatile memory switching at the same compliance. The nature of the filamentary switching is modeled through physical analysis and density function theory calculations. Pre‐forming driven oxygen vacancy concentration modulation is guiding the formation of Ag‐based hybrid filament and conducts the switching process. As a result, the device shows highly stable memory switching with tunable operating conditions, multiple storage levels and successfully overcome the endurance/retention dilemma with high endurance of >108 and >1‐day retention at 150 °C. This work establishes the possibility to design highly efficient metal‐filament based devices through proper tuning of nanoionics, which can fulfil the need of futuristic devices.