Memory mechanisms of nonvolatile organic bistable devices based on colloidal CuInS2/ZnS core–shell quantum dot – Poly(N-vinylcarbazole) nanocomposites

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 300 K 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.