Simulation Of Mechanical Properties Of Thin Films And Surface Morphology Influenced By ES Barriers

In recent decades,with the rapid development of nanomaterials science and technology,nanofilm has been widely used in various fields,such as information,energy and biology,due to its many excellent properties.However,the surface structure of the nanofilm will change because of the influence of external mechanical stress,temperature,pressure and defects,barriers inside the film.These tiny changes can cause fundamental alterations in the film performance,which is not conducive to the synthesis of the devices.Accordingly,it is a key for researching and fabricating nanofilms with high performance and stability.Nevertheless,it is difficult to control film growth in current experimental equipment to observe the nucleation mechanism and growth process at the atomic level.Therefore,it is a good method to use computer simulation technology to study the mechanical properties and growth process of thin films.Through this method,we can not only explore the growth mechanism and rules of nucleation,but also can greatly reduce the waste of resources in the experiment.This study is mainly divided into two parts.The first part is to study the mechanical properties of silver nanofilms with three different surface morphologies along the [0 1 0] crystallographic orientation simulated by Molecular Dynamics method.The second part is to study the effect of ES barriers and temperature on surface morphology in the process of two-dimensional copper film growth simulated by Monte Carlo method.The main simulation results are as follows:(1)The stretching process of three films are mainly divided into two periods,including elastic period and plastic period.In general,the ordinary film has a higher tensile resistance than the mesh films,and the square mesh film has a higher tensile resistance than the diamond mesh film.(2)With the increase of the thickness of the film,the initial stress decreases gradually,the yield strain slightly fluctuates;the yield stress and Young's modulus do not change basically.(3)With the increase of temperature,the yield strain,yield stress and Young's modulus of the film will decrease,and the decreasing trend is approximately linear.(4)The ES barrier affects the surface morphology of the film.Basically,the roughness of the film surface increases with the increase of 2D and 3D ES barriers.(5)There is a competitive relationship between the 2D and 3D ES barriers,and the value of 3D ES barrier of the competition point becomes smaller as the 2D ES barrier increases.(6)Temperature also affects the surface morphology of the film.Basically,the roughness of the film surface decreases with the increase of temperature.Therefore,we can extend the competitive relationship to any temperature,which has important guiding significance for experiments.