Electrical bistability by self-assembled gold nanoparticles in organic diodes

Abstract

Electrical bistability is reported in metal-organic-metal diodes. The device consists of two Al electrodes separated by a layer of 2-amino-4,5-imidazoledicarbonitrile that contains embedded Au nanoparticles (NPs) supported by parylene nanopillars. Electrical characterization of the device shows two well-defined states with high (off) and low (on) impedances. The on/off ratio is about 104. This conspicuous memory effect is rationalized in terms of charge storage mediated by the NP states. The fabrication method is general and provides a good control on both the size uniformity and the self-assembly of Au NPs embedded in the organic materials.