摘要
采用基于密度泛函理论的第一性原理方法对氧掺杂或修饰的硅[100]方向纳米线表面的电子结构和光学性质进行了研究,结果表明:氧掺杂或修饰对硅纳米线的几何构型、能带结构和光学性质都有一定的影响.掺氧后,硅纳米线晶胞体积减小、在掺杂氧原子近邻的Si-Si键长受到影响最大;硅纳米线的能隙变窄,其中修饰形成Si=O双键的硅纳米线能带上可看到明显的杂质带,且氧原子对带边电子态有贡献,可提高半导体发光效率;掺杂或修饰形成Si-O-Si桥键的硅纳米线介电常数受影响较小,而形成Si=O双键的介电峰值发生蓝移.该研究结果为制备发光硅纳米材料及器件提供理论参考.
The first principles based on density functional theory(DFT)was used to study the electronic structure and optical properties of oxygen doped or modified Si[100]oriented nanowires.The results show that oxygen doping or modification has certain effects on the geometry,band structure and optical properties of silicon nanowires.After doping with oxygen,the cell volume of silicon nanowires decreases,the Si-Si bond length near the doped oxygen atom is affected most,and the energy gap of silicon nanowires becomes narrower.Obvious impurity band can be seen in the energy band of Si=O bond modified silicon nanowires,and oxygen atoms contribute to the band edge electronic state,which can improve the semiconductor luminous efficiency.The dielectric constant of Si nanowires with Si-O-Si bridge bond formed by doping or modificationed is less affected,while the dielectric peak of Si=O double bond is blue shifted.The results provide a theoretical reference for the preparation of of luminescent silicon nanomaterials and devices.
作者
吴学科
张颂
黄意
WU Xueke;ZHANG Song;HUANG Yi(Kaili University,Kaili,Guizhou,556011,China)
出处
《凯里学院学报》
2020年第6期24-27,共4页
Journal of Kaili University
基金
贵州省教育厅自然科学研究项目(黔教合KY字[2019]183)。
关键词
第一性原理
掺杂
硅纳米线
First principles
doping
silicon nanowires
