金刚石(111)/Al界面形成及性能的第一性原理研究  

First-principles study of formation and performance of diamond(111)/Al interface

作　　者：孙士阳[1] 迟中波 徐平平[1] 安泽宇 张俊皓 谭心[1] 任元[1] Sun Shi-Yang;Chi Zhong-Bo;Xu Ping-Ping;An Ze-Yu;Zhang Jun-Hao;Tan Xin;Ren Yuan(School of Mechanical Engineering,Inner Mongolia University of Science and Technology,Baotou 014010,China)

机构地区：[1]内蒙古科技大学机械工程学院,包头014010

出　　处：《物理学报》2021年第18期329-335,共7页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:61765012);内蒙古自治区自然科学基金(批准号:2020LH08009,2019LH05009);内蒙古自治区高等学校科学研究项目(批准号:NJZY20099)资助的课题.

摘　　要：针对金刚石/Al界面的形成和性能,采用第一性原理计算方法,研究了Al原子在H终止金刚石表面的吸附及其迁移行为,以及金刚石/Al界面的结构与黏附功.结果表明:Al原子吸附对金刚石原子表面结构不敏感,且表面迁移激活能非常小,其原因是Al与H原子间没有形成化学键,仅有少量电荷转移,为物理吸附;由吸附位置生长而形成的金刚石/Al界面为亚稳结构,不具有能量稳定性.本文结果为理解金属纳米掩膜的形成机理提供重要的理论参考.The simple and convenient metallic mask method is a significant method of preparing diamond nanostructures.The metallic mask method has poor repeatability and can not give the ideal results,because it is supported by no theory about formation of surface mental nanoparticles and its technological parameters are optimized by no experimental techniques that are expensive either.Aiming at the formation and performance of the diamond/Al interface,this paper adopts the first-principles to study the adsorption and migration behavior of Al atoms on the H-terminated diamond surface and the structure of the diamond/Al interface.The results show that the highest adsorption energy is at the T4 position,which is only 0.181 eV,through comparing the adsorption energies of Al atoms at the highly symmetrical positions(Top,Br,H3 and T4)on the surface of the H-terminated diamond(111).The adsorption energies at these different positions are similar and the maximum difference is only 0.019 eV.There is formed no chemical bond,although Al has partial charge transfer on the H-terminated surface through the analysis of differential charge density and worse layout distribution.This phenomenon can be considered as electrostatic adsorption.That is to say,the adsorption of Al atoms are physical adsorption.The smooth potential energy surface also makes it easier for Al atoms to migrate on the diamond surface.The calculation results reveal that the migration activation energies of the two possible migration paths(from T4 position to Br position and from T4 to Top position)are 0.011 eV and 0.026 eV respectively.The above results imply that the metal Al and diamond are mainly connected by weak force,so the adhesion work of the three diamond/Al interface structures is compared based on the geometric stacking structure.The results show that the adhesion work of the three interfaces is around 0.These results indicate that the stability of the diamond/Al interface is not high and the stable structure of the interface is easily destroyed when the ext

关 键 词：金刚石/铝界面 吸附性 激活能 第一性原理 

分 类 号：TQ163[化学工程—高温制品工业] TB306[一般工业技术—材料科学与工程]