Diffusion mechanism of nickel oxidation in conducting channel of Pt/NiO/Pt switching structure

A resistive switching effect based on the simple binary metal oxides has attracted considerable attention due to the possibility of its application in new electronic memory chips. A diffusion mechanism of nickel oxidation in the conductive channel of resistive switching memory structure Pt/NiO/Pt is studied. The developed model of this mechanism, built in the cylindrical geometry of the channel, is identical to the familiar model of freezing (or thawing) inside a hollow cylinder with a constant temperature on the inner surface. Numerical solution of a quasi-stationary approximation, which takes into account only the time dependence upon the movement of oxidation boundary, is consistent with the experiment. The analysis shows that the diffusion oxidation may be critical for the extinction of the channel’s metallic conductivity in switching structures based on nickel oxide and oxides of other transition metals.