Al高掺杂浓度对ZnO导电性能影响的第一性原理研究

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,在同等环境条件下,建立了未掺杂和三种不同浓度的Al原子取代Zn原子的Zn_1-xAl_xO模型,然后分别对模型进行了几何结构优化、总态密度分布和能带分布的计算.结果表明:ZnO高掺杂Al的条件下,随掺杂Al原子浓度增大,进入导带的电子增多,电子迁移率减小,电导率减小,导电性能减弱;但是随高掺杂Al的浓度减小,反而使电子迁移率增大,电导率增大,导电性能增强.计算得到的结果与实验中Al原子 关键词： Al高掺ZnO 电导率 浓度 第一性原理

Frist principles study of effect of high Al doping concentration of p-type ZnO on electric conductivity performance

We optimize the geometric structure and calculate total densities of states, band structures, the relative number of electrons and mobility ratios of electrons of ZnO mode established at different concentrations of Al, in the condition of high concentration of Al heavily doped ZnO semiconductor at low temperature, by adopting the ab-initio study of plane wave ultra-soft pseudo potential technique based on the density function theory (DFT). It is found that the relative number of electrons increases, but the mobility ratio of electrons of ZnO decreases, with the concentration of Al increasing. On the contrary, the lower the Al doping concentration, the stronger the conductivity of ZnOis. The conductivity is compared. We can draw a conclusion that the conductivity of ZnO semiconductor decreases with Al doping concentration increasing. The calculation results are consistent with the change trend of experiments with Al concentrations exceeding o.z, i.e., x≥0.02.