Writing and erasing mechanisms of stable nonvolatile memory devices based on SnO2 nanoparticle/polystyrene nanocomposites.

X-ray photoelectron spectroscopy spectra and transmission electron microscopy images showed that SnO2 nanoparticles were randomly distributed in the polystyrene (PS) layer. Capacitance-voltage (C-V) measurements on the Al/SnO, nanoparticles embedded in PS layer/p-Si devices at 300 K showed a clockwise hysteresis with a large flatband voltage shift due to the existence of SnO2 nanoparticles. Capacitance-time measurements showed that the devices exhibited excellent memory retention characteristics at ambient conditions. The writing and the erasing mechanisms for the Al/SnO, nanoparticles embedded in PS layer/p-Si devices are described on the basis of the C-V results and energy band diagrams.