Abstract: Resistive random access memory (ReRAM) is one of the most promising candidates for next generation high speed nonvolatile memory devices. Bi₂O₃ thin films were deposited on heavily doped silicon wafer by RF magnetron sputtering, and the crystalline structure of the Bi₂O₃ thin films were characterized by XRD. The resistive switching characteristics of the Au/Bi₂O₃/n⁺Si/Al structure and the dependence of the ReRAM behavior on the thickness of the Bi₂O₃ thin films were studied. XRD analysis shows that the Bi₂O₃ thin films have good crystalline quality with (201) preferential orientation, while I-V curves results indicate that Bi₂O₃ thin films exhibit reversible and steady unipolar resistive switching behaviors. It is further found that the forming voltages, set voltages, and reset voltages depend linearly on the thickness of Bi₂O₃ thin films, and for the device with the thickness of 31.2 nm, these three threshold voltages are all below 4 V, which meet the need of low voltage operation of the memories.

Key words: Bi₂O₃ thin film, resistive switching, thickness dependence