Study On Preparation And Properties Of Graphene Oxide Based Transparent Resistive Random Access Memory

With the rapid development of information technology and the miniaturization of electronic products,the development of high speed and high density flexible and transparent non-volatile memory has become an inevitable trend.Resistance Random Access Memory?RRAM?has attracted wide attention due to its advantages of high memory density,low power consumption and fast reading and writing speed.Graphene oxide?GO?obtained through graphene oxidation presents semiconductor properties due to the presence of oxygen-containing functional groups.Among numerous resistive materials,carbon based RRAM devices with GO as the dielectric layer have become one of the most promising candidates due to their high density and low energy consumption.Based on the above analysis,in this paper,we studied the resistive switching of based-GO RRAM devices by doping oxide nanoparticles,and discussed the mechanism of the resistive switching.The main conclusions are as follows:?1?A series of GO films were prepared on a transparent and flexible ITO-PET substrate by spin coating method.Then a series of Ag/GO/ITO/devices were obtained with Ag as the top electrode.The effect of GO suspension concentration on the resistive switching of the Ag/GO/ITO/device was studied.The results showed that Ag/GO/ITO/devices fabricated with different GO suspension concentrations were all of bipolar resistive switching.When the GO suspension concentration is 2 mg/mL,the resistance ratio of Ag/GO/ITO/device is the largest?about 52 times?,fatigue and retention are excellent,the distribution of SET and RESET voltage is concentrated.Through the I-V log-log coordinate curve,raman spectra of high resistance state and low resistance state,and element distribution of the film section,it is confirmed that the mechanism of resistive switching of Ag/GO/ITO/device is derived from the migration of oxygen ions in GO film under electric field,that is,the formation and fracture of SP² conductive filaments,rather than the formation and fracture of Ag conductive filaments.?2?Adding different amounts of TiO₂ nanoparticles into GO suspension by ultrasonic dispersion,then a series of GO-TiO₂ mixed suspensions were obtained.A series of GO-TiO₂ thin films were prepared on ITO-PET substrate by spin coating,and Ag/GO-TiO₂/ITO devices were obtained with Ag as the top electrode.The effect of different amount of TiO₂ nanoparticles on the resistive switching was studied.The results showed that,when the content is 15%,TiO₂ nanoparticles are most uniformly dispersed in the film,and the resistance ratio of Ag/GO-TiO₂/ITO devices is the largest?about 112 times?.Compared with Ag/GO/ITO/devices,the SET and RESET voltages decreased by 67%and 62%respectively,which greatly reduced the power consumption.The larger resistivity ratio and low voltage of Ag/GO-TiO₂/ITO device were the result of the simultaneous migration of oxygen ions in TiO₂ and GO under the electric field.?3?Ag/GO-ZnO/ITO devices were prepared on ITO-PET substrate with Ag as the top electrode by ultrasonic dispersion and spin coating with 15%amount of ZnO nanoparticles,the resistive switching of the device was studied.The results showed that ZnO nanoparticles were uniformly dispersed in the film.The resistivity ratio of Ag/GO-ZnO/ITO device reached 324 times,more than 6 times that of undoped ZnO nanoparticle devices,and more than 3 times that of ZnO nanorod doped GO devices?Al/GOZNs/ITO?reported in the previous literature.The resistance mechanism of the device is derived from the formation and fracture of SP² conducting filaments.