Co掺杂6H-SiC的第一性原理研究  

First-principles study of Co-doped 6H-SiC

作　　者：吴磊 王嘉豪 刘淑平[1,2] WU Lei;WANG Jia-Hao;LIU Shu-Ping(School of Applied Science,Taiyuan University of Science and Technology,Taiyuan 030024,China;The Second Research Institute of China Electronics Technology Group Corporation,Shanxi Key Laboratory of Wide Band gap Semiconductor Materials,Taiyuan 030024,China)

机构地区：[1]太原科技大学应用科学学院,太原030024 [2]中国电子科技集团公司第二研究所宽禁带半导体材料制备山西省重点实验室,太原030024

出　　处：《原子与分子物理学报》2023年第5期155-160,共6页Journal of Atomic and Molecular Physics

基　　金：宽禁带半导体材料山西省重点实验室开放基金(201712)。

摘　　要：此文用第一性原理密度泛函理论(DFT)的广义梯度近似(GGA)的平面波赝势法(PBE),计算了未掺杂及Co替位Si掺杂的6H-SiC体系的电子结构与光学特性,获得了Co掺杂将导致6H-SiC由带隙为2.016 eV的间接带隙半导体变成带隙为0.071 eV的p型半导体,且有磁性;掺杂后能带结构中出现由Co的3d能级造成的杂质能级;且载流子浓度提升,使得材料的导电性得到提高;替换掺杂使得6H-SiC在光学性质方面有所变化,介电函数实部和虚部在低能级处增大,吸收光谱从未掺杂的3.2 eV开始吸收变为略高于0 eV就开始;反射谱与电导率曲线发生红移等有益结果.A plane-wave pseudopoten tial method(PBE)for generalized grodient approximation(GGA)of first principles density functional theory(DFT)is adopted to calculate the electronic structures and optical characteristics of the intrinsic and Co(replacing Si)doped 6 H-SiC systems.It is shown that Co doping will change 6 H-SiC from indirect band gap semiconductor with band gap of 2.016 eV to p-type semiconductor with band gap of 0.071 eV and lead it to be magnetic.The impurity energy levels in the band structure after doping is caused by the 3 d energy levels of Co;the carrier concentration which improves the electrical conductivity of the material.Replacement doping makes a change in 6 H-SiC optical properties,the real and imaginary parts of the dielectric function increase at low energy levels,and the absorption spectrum changes from 3.2 eV to slightly more than 0 eV.The reflection spectrum and electrical conductivity curve are red-shifted.The conductivity of 6 H-SiC is enhanced by doping,making its application in infrared light more extensively.

关 键 词：6H-SIC 带隙 电子结构 光学特性 

分 类 号：O734[理学—晶体学]