Facile strategy for the fabrication of efficient nonvolatile bistable memory devices based on polyvinylcarbazole– zinc oxide

Abstract

This paper describes the development of polyvinylcarbazole– ZnO hybrid nanocomposites (PVZ) comprising electron donor carbazole moiety (p-type) and electron acceptor zinc oxide (ntype) by a facile strategy and demonstrated its application as an active layer in the nonvolatile memory device. The structure and composition of the nanocomposite were studied by UVVisible absorption, photoluminescence, Raman, FT-IR, XRD, SEM, HR-TEM, and AFM. The results suggested that ZnO retains its hierarchical supramolecular porous morphology and wurtzite crystalline phase with defect states in the PVZ hybrid nanocomposite. PVZ exhibited good solubility in dichlorobenzene and memory devices were fabricated by sandwiching PVZ nanocomposites between indium tin oxide and silver electrode (ITO/PVZ/Ag). The conduction mechanism in the devices was manifested by fitting the double logarithmic I–V plots. Slope value of I–V plots suggested conduction mechanism in the devices was followed Ohmic, Poole–Frenkel emission, and trap filled space charge limited conduction which depends on the applied voltage. Endurance performances of the devices were stable for more than 100 cycles having ON/OFF current ratio of 5.2 103 and retention time of 105 s.