High-performance nonvolatile write-once-read-many-times memory devices with ZnO nanoparticles embedded in polymethylmethacrylate

A mixture of ZnO nanoparticles and polymethylmethacrylate was used as an active layer in a nonvolatile resistive memory device. Current-voltage characteristics of the device showed nonvolatile write-once-read-many-times memory behavior with a switching time on the order of s. The device exhibited an on/off ratio of > 10 4, retention time of > 10 5s, and number of readout of 4 × 10 4 times under a read voltage of 0.5 V. The emission, cross-sectional high-resolution transmission electron microscopy (TEM), scanning TEM-high angle annular dark field imaging, and energy dispersive x-ray spectroscopy elemental mapping measurements suggest that the electrical switching originates from the formation of conduction paths. © 2011 American Institute of Physics.