ZnO高掺杂Ga的浓度对导电性能和红移效应影响的第一性原理研究

采用基于密度泛函理论框架下的第一性原理平面波超软赝势方法，在相同环境条件下建立了浓度不同的由Ga原子取代Zn原子的Zn_1-xGa_xO模型.对低温高掺杂Ga原子的Zn_1-xGa_xO半导体的能带结构、态密度和吸收光谱进行了计算.结果表明:Ga原子浓度越大，进入导带的相对电子数越多，但是电子迁移率反而减小.通过对掺杂和未掺杂ZnO的电导率以及最小间隙带宽度分别进行了比较 关键词： ZnO高掺杂Ga 电导率 红移 第一性原理

Effects of the concentration of Ga high doping on electric conductivity and red shift of ZnO from first principles

We present the band structures and densities of states and calculation of absorption spectrum as well as the relative number of electrons and mobility ratio of electrons scattering from Zn_1-xGa_<em>xO with different concentration of Ga,and in the condition of high concentration of Ga heavily doped in ZnO semiconductor at low temperature,by adopting the ab-initio plane wave ultra-soft pseudo potential technique based on the density functional theory. It was found that the relative number of electrons increases with the concenteation of Ga increasing,but the mobility ratio of electrons of Zn_1-xGa_<em>xO decreases. The conductivity and minimum band gaps of the doped and undoped ZnO have been compared respectively,from whichwe draw the conclusion that the conductivity of Zn_1-xGa_<em>xO semiconductor decreases with the concentration of Ga increasing. When the concentration of Ga reaches a certain value,the minimum band gap dreases with the concentration of Ga increasing,and the phenomenon of red shift happens in the high energy zone. Calculations is in agreement with the experimental results obtained in Zn_1-xGa_<em>xO with atomic Ga doping in excess of x=0.04.