Three-dimensional Thermal And Stress Simulation And Analysis Of Molybdenum Disulfide Interlayer Phase Change Memory Cell

In the research of next-generation non-volatile memory devices,phase-change memories stand out for their high read/write speed and high reliability.The phase change memory is based on the large difference in resistance between the crystalline and amorphous states of the phase change material.In operation,the Joule heat generated by the different current pulses is used to reversibly convert the phase change material between the crystalline state and the amorphous state,thus realizing the storage of phase change memory.Since phase change memories rely on thermal effects,they are accompanied by large temperature changes during their operation,and thermal analysis and strain and stress analysis caused by thermal expansion are important.In semiconductor memory,power consumption and service life have always been important performance indicators.In this paper,a two-dimensional material with small thermal conductivity,molybdenum disulfide,is used as a spacer to construct a new model for thermal and mechanical analysis.Based on the finite element method commonly used in engineering projects,this paper uses Ansys Workbench to construct and solve the 3D model of phase change memory cells.T-type structure and layered structure were established under the same conditions,and the electrothermal and thermal stress were simulated.The main ways of heat loss were explored,and the temperature distribution,deformation and stress change were analyzed.Then the T-structure and layered structure with the molybdenum disulfide interlayer were constructed and simulated.The thermal and mechanical parameters of the two new structures were obtained and compared with the traditional structure.The results of simulation analysis show that the molybdenum disulfide interlayer canimprove the thermal efficiency of the phase change unit and reduce the Reset current,whether it is T-structure or layered structure.At the same time,in the mechanical analysis,the addition of molybdenum disulfide interlayer also makes the stress of the phase change layer is smaller,that is,the damage of the internal stress to the phase change unit can be reduced,and the working life of the phase change memory unit is longer,especially in the layered structure,the reduction of the stress is more obvious.The role of molybdenum disulfide barrier in the two structures was further analyzed,and the reasons for improving the thermal efficiency of phase change memory cells and reducing the internal stress were found.In addition,the addition of the molybdenum disulfide interlayer can reduce heat loss,that is,reduce the influence on adjacent cells,which has a certain degree of improvement on the problem of thermal disturbance in the memory cell array.