Carrier mechanism of ZnO nanoparticles-embedded PMMA nanocomposite organic bistable memory device

Abstract

ZnO nanoparticles embedded polymethylmethacrylate (ZnO-PMMA) organic bistable memory device was fabricated by sol-gel spin coating technique. ZnO-PMMA thin films were deposited on ITO coated glass substrates (Al/ZnO-PMMA/ITO). XRD and SAED patterns of ZnO-PMMA nanocomposite thin films showed the polycrystalline behavior. FTIR peaks of ZnO-PMMA nanocomposite thin films were observed at 540 cm−1 for Zn–O bond and at 1766 cm−1 for ester carbonyl CO stretch vibration of PMMA. The bandgap of ZnO-PMMA thin films was observed to be lower (3.07 eV) than the pure ZnO (3.20 eV), while the PL peak was observed at a wavelength of 403 nm. Current-voltage (I–V) measurements of the device, Al/ZnO-PMMA/ITO showed a nonvolatile electrical bistable behavior at room temperature. The ON to OFF current ratio of the bistable device was found to be ~104, which confirmed the write and the read sequence and discussed the carrier transport mechanism.