Humidity effects on the redox reactions and ionic transport in a Cu/Ta2O5/Pt atomic switch structure

Tohru Tsuruoka, Ilia Valov, Cedric Mannequin, Tsuyoshi Hasegawa, Rainer Waser, Masakazu Aono

    Research output: Contribution to journalArticlepeer-review

    28 Citations (Scopus)


    Redox reactions at the Cu/Ta2O5 interface and subsequent Cu ion transport in a Ta2O5 film have been investigated by means of cyclic voltammetry (CV) measurements. Under positive bias to the Cu electrode, Cu is preferentially oxidized to Cu2+ and then to Cu+. Subsequent negative bias causes a reduction of the oxidized Cu ions at the interface. It was found that CV curves change drastically with varied relative humidity levels from 5 to 85%. At higher humidity levels, the ion concentrations and diffusion coefficients, estimated from the CV curves, suggest increased redox reaction rates and a significant contribution of proton conduction to the ionic transport. The results indicate that the redox reactions of moisture are rate-limiting and highlight the importance of water uptake by the matrix oxide film in understanding and controlling the resistive switching behavior of oxide-based atomic switches.

    Original languageEnglish
    Article number06GJ09
    JournalJapanese Journal of Applied Physics
    Issue number6
    Publication statusPublished - 2016 Jun 1

    ASJC Scopus subject areas

    • Engineering(all)
    • Physics and Astronomy(all)


    Dive into the research topics of 'Humidity effects on the redox reactions and ionic transport in a Cu/Ta<sub>2</sub>O<sub>5</sub>/Pt atomic switch structure'. Together they form a unique fingerprint.

    Cite this