Nonvolatile multilevel memory effect in Cu/WO3/Pt device structures

The multilevel storage properties of Cu/WO3/Pt structure devices are demonstrated. By the application of suitable compliance current values, the Cu/WO3/Pt memory device can be driven to various resistance states. Some distinguishable states are reproducible over 100 dc switching cycles, and such states remain stable over 104 seconds. The multilevel memory effect in the Cu/WO3/Pt device can be attributed to the combination of the radial growth of filaments and the formation of more conductive filaments when applying a higher compliance current during the set process. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)