DOI: https://doi.org/10.29363/nanoge.neumatdecas.2023.026
Publication date: 9th January 2023
The resistance state of filamentary memristors is tuned by relocating only a few atoms at interatomic distances in the active region of the conducting filament. Thereby the technology holds great promises not only in its ultimate downscaling potential and energy efficiency but also in unprecedented operation speed. In spite of an ongoing interest and recent achievements demonstrating sub-100 ps resistive switching, the breakthrough toward telecommunication frequency applications still lacks the clarification of the dominant mechanisms and inherent limitations of ultra-fast resistive switching.
By utilizing current state of the art electronics, we present the current world record resistive switching speed and multilevel programming in tantalum-pentoxide based memristors due to 20 ps long set and reset voltage pulses, confirmed by the evaluation of the steady states before and after the programming pulses. More importantly, we move beyond the common approach of verifying the effect of the programming pulses in the established steady state only: We have developed an optimized sample design which enabled us, for the first time, to monitor the dynamics of the resistive switching also during the ultra-short programming voltage pulses. Thereby set times well below 20 ps pulse durations could be measured at picosecond resolution. A thermal delay of the reset transition, which exceeds the reset voltage pulse duration, was discovered and the electric field induced and diffusion driven resistive switching mechanisms were experimentally separated [1].
Our results underline the importance of the thermal optimization of atomic scale resistive switches for applications requiring fast cyclic operation. This enables the integration of valence change based filamentary resistive switches as fast and low-power components into state-of-the-art telecommunication technologies.
This work was supported by the Werner Siemens Stiftung. M.C. acknowledges financial support from the Swiss National Science Foundation under the Spark Project Nr. 196486. A.H. acknowledges the NKFI K128534 grant.