SiC基底覆多层石墨烯力学强化性能分子动力学模拟  

Molecular dynamics simulation of mechanical strengthening properties of SiC substrate covered with multilayer graphene

作　　者：陈晶晶 赵洪坡 王葵[2] 占慧敏 罗泽宇 Chen Jing-Jing;Zhao Hong-Po;Wang Kui;Zhan Hui-Min;Luo Ze-Yu(School of Mechanical and Electrical Engineering,Nanchang Institute of Technology,Nanchang 330044,China;School of Computer and Information Engineering,Nanchang Institute of Technology,Nanchang 330044,China)

机构地区：[1]南昌理工学院机电工程学院,南昌330044 [2]南昌理工学院计算机信息工程学院,南昌330044

出　　处：《物理学报》2024年第10期372-382,共11页Acta Physica Sinica

基　　金：江西省教育厅科学技术研究(批准号:GJJ2202705);南昌理工学院校级课题(批准号:NLZK-22-07,NLZK-22-01)、南昌理工学院机械表/界面摩擦磨损与防护润滑研究中心资助的课题;南昌市重点实验室建设项目(批准号:2020-NCZDSY-005)。

摘　　要：微机电系统半导体SiC器件覆多层石墨烯的力学强化性能与塑性变形微观研究,将对提升该器件耐久性服役寿命期和强韧化机制理解起到显著作用.因此,本文基于分子动力学法探讨了石墨烯堆垛类型(AA和AB堆垛)和极端使役温度对其接触力学性能(最大承载荷、硬度、杨氏模量、接触刚度)、微结构演化、接触质量、褶皱形貌、位错总长的影响,解释了SiC基底覆多层石墨烯力学强化的原子尺度机制.研究发现:相同使役温度下,随覆石墨烯层数增加,SiC基底微结构的棱柱形位错环演化中越早发生脆断;石墨烯AB堆垛在最大压深时的C-C键断裂会导致石墨烯优异面内弹性变形丧失,以致其最大承载性呈现断崖式下降.研究表明:SiC基底覆三层石墨烯的力学强化性能是纯SiC的2倍,该强化效应不受石墨烯堆垛类型影响,其力学强化机制主要源于多层石墨烯受载加大会引起石墨烯面内褶皱增大,从而增大界面接触刚度,触发界面接触质量减小所致.使役温度升高,会激发原子振动频率增大,诱导界面接触原子数增多,以致界面接触质量增大,而界面接触刚度随之减弱,最终引起SiC基底覆多层石墨烯力学性能随温度升高呈近似直线下降.此外,SiC基底的亚表层应力集中会诱导基底内的微结构产生滑移与演变;基底覆石墨烯层数增加可有效减小基底亚表层的应力集中分布程度,从而对基底起抗载保护作用.A large number of practices have shown that under the coupling influence of complex working conditions and frequent reciprocating contact,the surfaces of semiconductor devices in micro/nano electromechanical systems often produce adhesive wear,which is the essential reason resulting in short durability service life and declining contact mechanical properties for microelectronics semiconductor devices.However,graphene can significantly improve the interface properties of mechanical components and electronic components due to its excellent mechanical properties,such as high carrier concentration,good thermal conductivity,and low shear.Thus,the study of mechanical strengthening properties and plastic deformation of SiC material with covered multi-layer graphene in MEMS devices will play a significant role in improving the durability service life of MEMS device,and understanding its strengthening and toughening mechanism.Therefore,this paper studies and discusses the effects of stacking type and extreme service temperature with low and high levels on the contact mechanical properties(maximum load,hardness,Young modulus,contact stiffness),micro-structure evolution,contact mass,fold morphology,and total length of dislocation.The atomic-scale mechanism of enhanced mechanical properties of SiC material with multi-layer graphene is explained.The research shows that the damage to carbon-carbon bond at the maximum indentation depth will lead graphene to lose the excellent in-plane elastic deformation capability when the graphene stacking type is AB stacking,so that the maximum load-bearing capacity of the substrate covered by three layers of graphene will drop linearly.In addition,the mechanical property of SiC material coated with three graphene layers is twice that of pure SiC substrate,and the strengthening mechanism is mainly due to the increase of wrinkle caused by the increase of multilayer graphene loading,which causes the quality of contact between the SiC substrate and the virtual indenter to decrease,thus increasi

关 键 词：SIC 多层石墨烯 力学强化 分子动力学 接触刚度 

分 类 号：TB332[一般工业技术—材料科学与工程]