Study On Memory Diode Devices Based On Organic Polymer Materials

The emergence of organic bistable devices (OBDs) provides us a low-cost solution of growing demand for storage device in the information society. Studying on nano or molecular devices provides a broad development space for storage devices, and the realization of multi-level storage further improves the storage density in unit device. These advantages are incomparable by inorganic memory devices. While the polymer is the most important research area in organic materials, and has been widely used in human’s life, so it’s a great significance to study the characteristics of the memory devices based on polymer materials. This article realized2,3,4level storage characteristics based on polymer memory devices respectively, and the storage mechanism are investigated.(1) The storage characteristics of polymer PVK-TF, PPDA-PVK, PFPS are investigated. Both PVK-TF and PPDA-PVK have carbazole groups, while contains TF and PPDA group respectively, which achieved2,3level storage characteristics Type Flash storage function respectively. PFPS is a kind of π-stacked polymer based on typical insulation material polystyrene with carbazole group, using which a Flash type memory device is achieved. It’s proved that the electrical storage performance of the devices can be adjusted through the introduction of functional groups in the polymer molecular chain. The understanding of the change of conformation mechanism has been strengthening.(2) Memory devices based on polymer PVK with nanoparticles were investigated, and3level storage characteristics type Flash storage function were achieved based on the devices. Current of the State "off’,"on-1","on-2" is in the magnitude of10-7A,10-4A-10-6A,10-2A-10-1A respectively, with larger switch ratio and duration time. It was found that the interface effect and field induced charge transfer were the reason for the change of conductive state in devices.(3) Finally, based on the interface effect, conformational transition theories we achieved a4levels Flash type memory device based on the polymer PVK-FK. Current of the Sate "off,"on-1","on-2","on-3" is in the10-8A,10-6A,10-4A,10"2A magnitude respectively. This article also had a try to take the reduced oxide-graphene as the top electrode. This method is a simple way to achieve the flexible and transparent devices. The experiment had achieved a dynamic random access memory device with switch ratio of103.