Fabrication and Characterization of Copper Oxide Resistive Memory Devices

Three synthesis techniques have been explored as routes to produce copper oxide for use in resistive memory devices (RMDs). The major results and their impact on device current-voltage characteristics are summarized. The majority of the devices fabricated from thermally oxidized copper exhibited a diode-like behavior independent of the top electrode. When these devices were etched to form mesa structures, bipolar switching was observed with set voltages <2.5 V, reset voltages <(-1) V and R OFF /R ON ∼10 3 -10 4 . Bipolar switching behavior was also observed for devices fabricated from copper oxide synthesized by RT plasma oxidation (R OFF /R ON up to 10 8 ). Voiding at the copper-copper oxide interface occurred in films produced by thermal and plasma oxidation performed at ≥200°C. The copper oxide synthesized by reactive sputtering had large areas of open volume in the microstructure; this resulted in short circuited devices because of electrical contact between the bottom and top electrodes. The results for fabricating copper oxide into ≤100 nm features are also discussed.