Resistance Switching Characteristics Of Cu Oxide Film And CuO Nanowire Devices

The resistive switching properties of copper oxide nanowire and copper oxide thin film devices were studied.Firstly, CuO nanowires(CuO NWs) were fabricated with thermal oxidation method and CuO NWs resistive random access memory(RRAM) devices were assembled with liquid-dropping technique. Surface morphology and electrical properties were characterized. It is found that these one-dimensional CuO NW RRAM devices showed resistive switching characteristics. This phenomenon could be explained with Joule heating of conductive filament.Secondly, Cu oxide films with different oxygen content were deposited with DC magnetron sputtering under different oxygen partial pressure. X ray diffraction(XRD) and transmission spectrum showed that, as oxygen content increase, the thin film changed from pure Cu2 O to Cu2 O and CuO mixture, and then the pure CuO.Finally, Cu oxide film RRAM devices, which was consisted of different electrode materials(Ag, Cu), different spatial structure(planar structure, three-dimensional structure) and different oxygen content(CuO, Cu2O), were studied. It was found that: 1) the switching characteristics is not obvious in Cu oxide film RRAM with planar structure;2) Bipolar resistive switching was observed in both Cu and Ag electrode devices, but unipolar resistive switching could be observed in Cu electrode devices only. And the RH/RL ratio was higher in devices with Cu electrode. 3) Comparing with Cu2 O film RRAM devices, CuO film RRAM devices were more stable and exhibited better controllability and toleration properties. 4) all above characteristics can be explained with Joule heating of conductive filament.