厚度对Bi薄膜表面特性和电学性质的影响-金属学报.PDF

第54 卷 第6 期 Vol.54 No.6 2018 年6 月 ACTA METALLURGICA SINICA Jun. 2018 厚度对Bi 薄膜表面特性和电学性质的影响 1 2 2 董彩虹 刘永利 祁 阳 1 东北大学理学院 沈阳 110819 2 东北大学材料科学与工程学院 沈阳 110819 摘要 基于第一性原理计算方法研究了厚度对(00l)和(012)取向Bi 薄膜稳定性、相变及导电性的影响。计算结 果表明，随着厚度的增加，(00l)取向Bi 薄膜稳定性增强，且薄膜偶数层稳定性优于奇数层；(012)取向Bi 薄膜稳 定性随着厚度的增加而降低，且在层数为4 时，表面能与偶数层(00Ɩ)取向的薄膜相当，预示二者在该厚度时较 易发生相变，分析认为与薄膜加厚过程中表面态的影响有关。随着厚度的增加，(00Ɩ)和(012)取向的Bi 薄膜表 现出从半导体转变为金属的特性。 关键词 Bi 薄膜，厚度，稳定性，相变，导电性，第一性原理计算 中图分类号 O484.4 文章编号 0412-1961(2018)06-0935-08 Effect of Thickness on the Surface and Electronic Properties of Bi Film 1 2 2 DONG Caihong , LIU Yongli , QI Yang 1 College of Science, Northeastern University, Shenyang 110819, China 2 School of Materials Science and Engineering, Northeastern University, Shenyang 110819, China Correspondent: QI Yang, professor, Tel: (024 E-mail: qiyang@imp.neu.edu.cn Manuscript received 2017-10-10, in revised form 2018-01-08 ABSTRACT Bismuth and its alloys exhibit a number of peculiarities and mysterious features due to its three-dimensional (3D) hexagonal crystal, and have attracted the interest of many researchers for many years. Currently, the trivial- to- topological and semimetal- semiconductor transitions have been focuse