Bipolar resistance switching in the Pt/WOx/W nonvolatile memory devices

We reported the resistive switching behavior in the Pt/WOx/W memory device fabricated with fully room temperature process. The devices show high resistance ratio (>140), reliable data retention at 85 °C and fast switching (100 ns). The field-induced resistance change can be explained based on the formation/rupture of the conduction filaments, due to migration of oxygen vacancies under electric field. The dominant conduction mechanisms of low resistance state and high resistance state were verified by ohmic behavior and trap-controlled space charge limited current, respectively. We demonstrate the present device can be used for multi-bit operation either by compliance current or by reset voltage.