V掺杂CrSi2能带结构的第1性原理计算  

First-Principles calculation of the band structure of V-doped CrSi2

作　　者：周士芸[1] 谢泉[2] 闫万珺[1] 陈茜[2] 

机构地区：[1]贵州安顺学院物理系,贵州安顺561000 [2]贵州大学电子科学与信息技术学院,贵州贵阳550025

出　　处：《云南大学学报（自然科学版）》2009年第5期484-488,共5页Journal of Yunnan University(Natural Sciences Edition)

基　　金：国家自然科学基金资助项目(60566001);教育部留学回国科研基金资助项目(2005383);贵州省科技厅国际合作项目资助(2005400102);安顺市科技计划项目资助(20082021)

摘　　要：采用基于第1性原理的密度泛函理论(DFT)赝势平面波方法和广义梯度近似,计算了V掺杂CrS i2体系的能带结构和态密度,计算结果表明,本体CrS i2是具有ΔEg=0.35 eV狭窄能隙的间接带隙半导体,其费米面附近的态密度主要由Cr的3d层电子和S i的3p层电子的态密度决定;V替代Cr掺杂后,费米能级进入价带,费米面插在价带的中间,带隙变窄,且间接带隙宽度ΔEg=0.25 eV;掺杂后费米面附近的电子能态密度则由Cr的3d层电子、V的3d层电子和S i的3p层电子的态密度共同决定,掺杂后V原子成为受主,在价带顶附近贡献了一定数量的空穴,使掺杂后CrS i2的导电类型变为p型,提高了材料的电导率.The energy band structures and density of states of intrinsic CrSi2 and V - doped CrSi2 have been calculated using the first- principles pseudo -potential method based on density functional theory （DFT） with generalized gradient approximation （GGA）. The calculated results show that CrSi2 is an indirect transition semiconductor with its narrow energy gap of 0. 35 eV ; the density of state near the Fermi surface is mainly composed of Cr 3d and Si 3p state electron. After doping V, the Fermi level enters valence band,the width narrows with the indirect band gap width AEg = 0.25 eV. The density of state near the Fermi surface is mainly composed of Cr 3d, Si 3p and V 3d state electron. Atom V becomes the aeeeptor to contribute some holes at the top of valence band and CrSi2 change into p - type semiconductor and improves the electrical conductivity of material.

关 键 词：半导体材料 CrSi2 掺杂 能带结构 第1性原理 

分 类 号：O474[理学—半导体物理] O481.1[理学—物理]