Memory mechanisms of nonvolatile organic bistable devices based on colloidal CuInS(2)/ZnS core-shell quantum dot - Poly(N-vinylcarbazole) nanocomposites

Abstract

Organic bistable devices (OBDs) fabricated utilizing CuInS2 (CIS)/ZnS core?shell-type quantum dots (QDs) blended with a poly(N-vinylcarbazole) (PVK) layer were fabricated on polyethylene terephthalate (PET) substrates by using a spin-coating technique. Transmission electron microscopy images revealed that the CIS/ZnS QDs were distributed over the surface of the PVK layer. Current?voltage (I?V) curves for the Al/PVK+[CIS/ZnS QDs]/ITO/PET devices at 300K showed that the maximum ON/OFF ratio of the current bistability for the OBDs was as large as 3.9×104. Memory mechanisms for the OBDs fabricated on PET substrates are described on the basis of the I?V results.