Bipolar one diode–one resistor integration for high-density resistive memory applications

Abstract

Different from conventional unipolar-type 1D–1R RRAM devices, a bipolar-type 1D–1R memory device concept is proposed and successfully demonstrated by the integration of Ni/TiO_x/Ti diode and Pt/HfO₂/Cu bipolar RRAM cell to suppress the undesired sneak current in a cross-point array. The bipolar 1D–1R memory device not only achieves self-compliance resistive switching characteristics by the reverse bias current of the Ni/TiO_x/Ti diode, but also exhibits excellent bipolar resistive switching characteristics such as uniform switching, satisfactory data retention, and excellent scalability, which give it high potentiality for high-density integrated nonvolatile memory applications.