Preparation And Performance Of Flexible Transient Memristor Based On Natural Dielectric Materials

Transient electronic devices are a new type of electronic devices that can be quickly destroyed and lose its original shape,function,or stored information after conducting a specific function,.Transient electronic devices can be applied in the fields of reducing the E-waste pollution caused by electronic devices and the storage of confidential information.In addition,transient electronic devices made of non-toxic,harmless,and bio-safe materials can play an important role in implantable electronic devices and wearable electronic devices.As an electronic device for information storage,memristor has the advantages including simple structure,low manufacturing cost,large storage density,low energy consumption,repeatable and fast read-write capacity.It has been considered as a next-generation information storage device.In this thesis,we combined the concepts of transient electrons and memristors,prepared a transient memristor by using polyvinyl alcohol,a synthetic non-toxic polymer,as the substrate,biomaterials such as pectin and silk fibroin,as the dielectric layer,and silver as the electrodes.It was shown that the memristor has an excellent transient performance and can be quickly destroyed in an aqueous solution.At the same time,compared with other similar memristors,the memristor has a higher switching ratio and a lower operating voltage.Finally,the mechanism of resistance switch was analyzed and discussed by theoretical simulations.It was shown that the PVA substrate we prepared has good self-supporting ability,flexibility,water solubility,transparency and surface flatness,and its height-undulation of the surface was no larger than ± 3 nm,suggesting that it is suitable to be used as a substrate for a memristor.In addition,the PVA substrate showed a good thermal stability.The mass loss is less than 1% when the temperature was raised to 70 °C,It means that the PVA substrate was not easily damaged by the heat generated by the electronic device.The dissolution rate of the PVA substrate in the aqueous solution was roughly linear with its thickness,indicating that the destruction speed of the transient memristor could be controlled by adjusting the substrate thickness.The switch ratio of memristor using pectin as dielectric layer was as high as 108.The working voltage was only 1 V.The switch ratio of memristor using silk fibroin as dielectric layer was 104,and the working voltage is 1.4 V.These results showed that the mem ristor we prepared has low power consumption and excellent anti-misreading ability.Besides,the scanning electron microscope image and simulation calculations showed that the mechanism of resistance switch of the pectin memristor was conductive filament m echanism.Silver ions entered the pectin layer,the migration is mainly achieved by mutual attraction with the C=O of the carboxyl group.An external electric field can promote this migration process,but it can not significantly change the migration path.In summary,the transient memristor we prepared in this thesis has excellent and controllable transient behavior,and excellent performances.It has potential application in confidential information storage,wearable,or implantable electronic equipment,etc.