Al高掺杂浓度对ZnO禁带和吸收光谱影响的第一性原理研究

First-principles study on the effects of high Al doped on the band gap and absorption spectrum of ZnO

采用密度泛函理论框架下的第一性原理平面波超软赝势方法,建立了未掺杂与不同浓度的Al原子取代Zn原子的两种Zn_(1-x)Al_xO超胞模型,分别对模型进行了几何结构优化、态密度分布和能带分布的计算.结果表明:ZnO高掺杂A1的条件下,掺杂的A1原子浓度越大,间隙带越窄,蓝移越弱.计算结果和实验结果相一致.

According to the density functional theory, using first-principles plane-wave ultrasoft pseudopotential method, we set two different kinds of Zn1-xAlxO supercell models of substituting Zn atom with Al atom and optimige the geomertries for the two models. The total density of states and the band structures are also calculated. The results show that in a range of high doping concentration, when the doping concentration of Al atoms increases, the band gap will be decrease, blue shift will decrease, which accords with the experimental results.