Memristor And Synaptic Bionics Study Based On BaTiO₃ And Hf_0.5Zr_0.5O₂ Thin Films

In recent years,memristors have caused great research interest due to their unique nonlinear electrical properties,especially in the fields of resistive storage and synaptic bionics.However,the poor flexibility and high temperature stability of traditional memristive devices and the lack of controllability of conductive paths have led to a large dispersion of switching voltage,which has hindered the practical development of memristors.Therefore,the preparation of new memristors is the focus of research in the frontier.At the same time,because the ferroelectric memristors stored by polarization inversion have good storage characteristics,this article also researches the ferroelectric memristors accordingly and conducts the resistance switching mechanism caused by ferroelectricity and oxygen vacancies In-depth analysis.Based on metal oxide materials,this paper studies high-performance memristors and synaptic bionic functions.The main contents are as follows:Firstly,the research group prepared a Pd/BaTiO₃?BTO?/LaSrMnO₃?LSMO?structure-based flexible memory device based on mica substrate and studied its flexibility and high-temperature stability.This work produced a device with a 3 mm bend radius and still exhibited excellent electrical performance after bending 10⁴ times.In addition to stable switching characteristics and multi-resistance storage at room temperature,it still has excellent retention characteristics and state transition performance between high resistance?HRS?and low resistance?LRS?at a high temperature of 200°C.This work shows that the flexible memory device has the advantages of good high temperature stability,good bendability and durability,and therefore has great research value.Secondly,Hf_0.5Zr_0.5O₂?HZO?thin film memory devices with different crystal orientations were prepared and the switching characteristics of different devices were explored.The experimental results show that compared with ordinary polycrystalline devices,preferentially oriented HZO thin-film devices have the advantages of lower switching voltage dispersion,longer data retention time,and better multi-level memory functions.The study also found that preferentially oriented HZO thin film devices can successfully simulate biological synaptic functions.This work shows that controlling the experimental conditions to produce high-quality HZO films can improve the electrical performance of memory devices,help solve the problem of large dispersion of switching parameters,and facilitate the further development of memristive devices.Thirdly,the effect of strain on HZO films was studied in this work.The test results show that the polarization reversal voltage and resistance switch characteristics are different with different strain.In this study,HZO films with different oxygen concentrations were also prepared by controlling the oxygen pressure.Based on the test results,it is reasonable to propose that the complex mechanism of resistance conversion behavior of HZO thin film may be caused by the joint participation of ferroelectricity and oxygen vacancy migration.The study also found that HZO films can successfully simulate learning behavior similar to the human brain.These results may help stimulate basic research on HZO-based ferroelectric semiconductor oxide thin film memristors and their potential applications in next-generation artificial electronic synaptic devices.