Study On Reliability Improvement And Multi-Functionalization Of CH₃NH₃PbI₃ Perovskite Resistive Switching Memory

In recent years,due to the rise of new technologies such as cloud computing and the Internet of Things,as well as the continuous popularization of electronic products such as mobile phones,computers,and digital cameras,new data storage technologies are very essential to meet the demand for big data.Memory is an important part of electronic equipment,which can store programs and data.Traditional non-volatile floating-gate-based flash memory has reached the technical bottleneck and cannot meet the growing demand for big data storage,due to the advent of the 32nm technology node of the integrated circuit and the limitation of Moore's Law.Therefore,it is imperative to develop new high-density non-volatile memory devices.As one of the next-generation non-volatile memories,resistive random access memory?RRAM?has attracted wide attention from researchers due to its high memory density,fast transition speed,low power consumption,and compatibility with CMOS.The structure of the resistive switching?RS?memory is generally a electrode/switching layer/electrode,the RS mechanism usually can be attributed to the formation/rupture of nanoscale conductive filaments?CFs?in the switching layer.Thus,the RS characteristics of RRAM would highly dependent on the switching layer materials.The organic-inorganic hybrid perovskite materials have been studied in various photovoltaic devices such as solar battery due to their simple preparation method,high mobility,adjustable band gap,and excellent light absorption characteristics.Recently,the mixed ionic-electronic conduction ability of organic-inorganic hybrid perovskites offers opportunities for novel functions such as RRAM.This work are mainly on optimizing the RS reliability and expanded the functions of the memory device with CH3NH3PbI3 film as the switching layer.1.Reliability optimization:For the problem of the environment instability of CH₃NH₃PbI₃and high RS fluctuation caused by the random formation/rupture of the CFs,we developed a method to insert silver indium antimony tellurium?AgInSbTe?between the Ag electrode and the CH₃NH₃PbI₃ film as the buffer layer.On the one hand,AgInSbTe can protect CH₃NH₃PbI₃layer from the expose of oxygen and water in the air,and improve the service time of the device.On the other hand,AgInSbTe,as an Ag fast ion conductor,can control the injection of Ag ions into the CH3NH3PbI3 layer,localize the CF formation/rupture region,and consequencely improve the RS uniformity of the device.2.Multi-functional expansion:Inserting AgInSbTe can control the CF formation/rupture region,providing a possibility of three-state multi-level memory application.In addition,the degradability of Ag/CH3NH3PbI3/FTO devices and the potential of devices for safe data storage are illustrated by a simple water-soluble method.Finally,the switching layer was prepared on a flexible ITO substrate,and the bending experiment was carried out.The device still has good RS characteristics under bending state,indicating that the device has certain mechanical endurance and provided a broader prospect for the CH₃NH₃PbI₃-based electronic devices.