Research On Resistive Properties And Physical Mechanism Of Two-dimensional Tin Sulfide Thin Films Based On Ion Doping

Memory plays an important role in daily life,industrial production,information technology and other fields.In order to meet the needs of society,researchers continue to develop memory.Resistive memory(RRAM)has become one of the powerful competitors of new memory because of its high speed and high density storage potential.Due to the existing resistive material system is relatively simple,and most of the intermediate layer is metal oxide,so the development of more suitable for RRAM dielectric materials,improve the resistive transmission mechanism and prepare excellent performance of resistive devices has become one of the focus of academic and semiconductor industry.In this paper,tin disulfide(Sn S₂)is used as the resistance layer,based on ITO/Sn S₂/ITO structure device,the resistance device is prepared by the optimization of Sn S2 film deposition process,and the resistance layer is doped with Ca²⁺and Na⁺ions and the annealing temperature is changed.The effects of ion doping and annealing temperature on the resistance performance of ITO/Sn S₂/ITO devices were investigated in order to obtain high performance memory in sulfide resistant system.In this paper,the conductive glass ITO is used as the substrate and used as the lower electrode.The Sn S₂film is prepared by chemical method and deposited by physical spin coating.The upper electrode ITO is prepared by magnetron sputtering technology.The resistance performance of the device is tested by semiconductor data analyzer,and the device performance and resistance mechanism are discussed.In the experiment,SnS₂films were prepared by spin-coating method.By optimizing spin-coating parameters,the densest films prepared under the conditions of 5000rpm,dynamic spin-coating and 30s were determined.The films were characterized by XRD,UV-VIS,SEM,EDS,XPS and Raman tests.By designing the experimental doped ion(Ca²⁺),it is proved that Ca²⁺can effectively improve the resistance performance of ITO/Sn S₂/ITO device,and the ion concentration is the key factor to determine the durability and retention characteristics of the device data.Meanwhile,the annealing temperature gradient is set in the experiment.It is proved that the appropriate annealing temperature can guarantee the better crystallization growth of Sn S₂film and improve the resistance performance of the device.Finally,it is determined that the device has the most mild resistance process under the annealing condition of 0.5%doping and 300?,and the data durability test cycle of the device is successfully increased to 5000 times,and the data retention time is increased to more than 10⁴s.It has excellent resistance.The conductive filaments formed by doping Ca²⁺ions in the resistive material significantly improved the resistance conversion performance of the device.AFM current test further verified that the conductive filaments caused the resistance conversion.In addition,the influence of Na⁺doping on the resistance performance of the device was also studied.Compared with the resistance performance of the device before and after doping,it was found that Na⁺doping successfully improved Endurance and Retention characteristics of the device.The results show that Sn S₂films are potential RRAM two-dimensional dielectric materials and have great application prospects in the field of resistive memory.