表面钝化硅纳米线的能带结构  

Band Structures of Si Nanowires with Different Surface Terminations

作　　者：尤思宇[1] 王燕[1] 

机构地区：[1]清华大学微电子学研究所,北京100084

出　　处：《Journal of Semiconductors》2006年第11期1927-1933,共7页半导体学报（英文版）

基　　金：国家自然科学基金重大国际合作资助项目(批准号:90307016)~~

摘　　要：采用第一性原理的方法计算了不同尺寸的(100)硅纳米线在H饱和及F饱和下的电子结构.计算结果表明,F饱和与H饱和的(100)硅纳米线均为直接禁带半导体,但F饱和硅纳米线的禁带宽度和价带有效质量都远小于H饱和硅纳米线,这一现象可用价带顶的σ-n杂化效应来解释.计算结果还表明,H或F饱和的(100)硅纳米线的极限———硅单原子链则表现为间接带隙半导体,文中对这一现象进行了分析和讨论.（100） silicon nanowires （SiNW） with different sizes and different surface terminations are studied with first-principles calculation. The results show that the one dimensional band structures of （100） SiNW with H and F terminations are both direct bandgap semiconductors,but SiNWs with an F termination have a smaller band gap and valence effective mass than SiNWs with an H termination. This can be interpreted via the σ-n mixing effect,i, e. ,the non-bonding 2P electrons （n） of F atoms produce an important orbital mixing with the a valence electrons. We also predict from the calculations that the extreme of （100） SiNW-a 2 ×2 helical Si atom chain- is an indirect bandgap semiconductor. This prediction is explained at the end of this paper.

关 键 词：硅纳米线 表面钝化 氟化 能带 σ-n杂化 

分 类 号：O471.5[理学—半导体物理]