Highly-stable write-once-read-many-times switching behaviors of 1D-1R memristive devices based on graphene quantum dot nanocomposites.

One diode and one resistor (1D-1R) memristive devices based on inorganic Schottky diodes and poly(methylsilsesquioxane) (PMSSQ):graphene quantum dot (GQD) hybrid nanocomposites were fabricated to achieve stable memory characteristics. Current-voltage (I-V) curves for the Al/PMSSQ:GQDs/Al/p-Si/Al devices at room temperature exhibited write-once, read-many-times memory (WORM) characteristics with an ON/OFF ratio of as large as 104 resulting from the formation of a 1D-1R structure. I-V characteristics of the WORM 1D-1R device demonstrated that the memory and the diode behaviors of the 1D-1R device functioned simultaneously. The retention time of the WORM 1D-1R devices could be maintained at a value larger than 104  s under ambient conditions. The operating mechanisms of the devices were analyzed on the basis of the I-V results and with the aid of the energy band diagram.