Electrical switching and conduction mechanisms of nonvolatile write-once-read-many-times memory devices with ZnO nanoparticles embedded in polyvinylpyrrolidone

Abstract

We reported on the influence of zinc oxide nanoparticles (ZnO NPs) on the electrical bistable behavior of nonvolatile write-once-read-many-times (WORM) memory devices based on an indium-tin oxide/polyvinylpyrrolidone (PVP):ZnO NPs/aluminum (ITO/PVP:ZnO/Al) structure. The maximum ON/OFF current ratio of the nonvolatile WORM memory devices was approximately 3 × 103 and the devices remained in the ON state even after the applied voltage was turned off. In addition, reliability studies for response time and once write/continuous read operations of the optimal ZnO NPs concentration are presented. The response times of both rise-time and fall-time were about 3 and 6 μs respectively. The conduction mechanisms of all voltage regions of the device were analyzed by theoretical models and electron trapping in the ZnO NPs of the electron tunneling among a PVP matrix was discussed. © 2014 Elsevier B.V. All rights reserved.