The Influence Of Substrate On The Strain Distribution Of MoS₂ Film

In recent years,nanomaterials have been widely used and widely concerned because of their unique magnetic,catalytic,optical,electrical,mechanical and biological properties.The two-dimensional material is a kind of nano material,which refers to a electronics of material that can move freely in a non-nano scale in two dimensions,such as a superlattice,a nano thin film,a quantum well,and the like.Among them,MoS₂ is a two-dimensional material with broad application prospects in optoelectronic devices and nanoelectronics.As the demand for developing semiconductor devices continues to grow,strain engineering of two-dimensional materials has recently attracted interest.Growth on different substrates can result in different strains of MoS₂,which can affect device performance.Therefore,it is of great significance to study the influence of the growth substrate on the performance of the MoS₂ device and analyze the intrinsic relationship between the two.By studying the properties of this mechanics,the MoS₂ device will be made into functional components.The strain distribution of layered MoS₂ grown on Au,Cu,Al₂O₃,SiO₂ and Ni was simulated by finite element method.The results show that the deformation of base and MoS₂ in Y direction is different due to different Poisson's ratio of base materials.Due to different Young's modulus of the base,the strain difference between the base bottom and the top of molybdenum disulfide is different.In the expansion process,the tensile strain at the bottom of the Y direction is greater than the tensile strain at the middle,which will cause the strain at the base and the top to be higher than that at the middle.Therefore,Young's modulus and Poisson's ratio of base material are closely related to the strain distribution of MoS₂.According to the simulation results,the strain of MoS₂ on the substrate of Au and SiO₂ is small.the strain difference between the top of MoS₂ and the bottom of the substrate is large,so it was easy for MoS₂ to be peeled off.On the substrate of Al₂O₃,the substrate material has a high young's modulus which is close to MoS₂.The strain difference from the top of MoS₂ is similar than the bottom of the substrate.Therefore,among these materials,Al₂O₃ is more suitable for MoS₂ substrate material.By studying the strain field distribution of the substrate material,the nano materials can be better regulated and the related properties of the device can be improved.