掺杂对2H-CuAlO_(2)结构和性能影响的第一性原理研究

First-Principles Study on the Structure and Properties of Ca and Mg Doped 2H-CuAlO_(2)

采用基于第一性原理的广义梯度近似平面波超软赝势法,计算了p型透明导电氧化物2H-CuAl_(2)在不同浓度Mg和Ca掺杂下的晶体结构以及电子特性。结果表明,Mg和Ca掺杂2H-CuAl_(2)的晶胞参数a随着掺杂浓度的升高都逐渐增大,c都逐渐减小;并且相同掺杂浓度下,Ca掺杂对晶胞参数a和c的作用大于Mg。Mg和Ca掺杂后,2H-CuAl_(2)依然具有间接带隙,带隙值随掺杂浓度增大而增大,相同掺杂浓度下,Mg掺杂2H-CuAl_(2)的带隙值大于Ca。Mg和Ca掺杂后2H-CuAl_(2)的总态密度出现增加,随着掺杂浓度增大总态密度逐渐降低,掺杂对2H-CuAl_(2)费米能级附近的导带和价带影响不大。

In this paper,the crystal structure and electronic properties of p-type semiconductor oxide 2H-CuAl_(2) doped with Mg and Ca under different doping concentrations are calculated using the first-principles generalized gradient approximate plane wave super soft pseudopotential method.The results shows that,the cell parameter a of Mg and Ca doped 2H-CuAl_(2) increases gradually and c decreases gradually with the increasing doping concentration.And under the same doping concentration,the effect of Ca on doped 2H-CuAl_(2) is greater than that of Mg.It is calculated that Mg and Ca doped 2H-CuAl_(2) also have an indirect band gap,and the band gap increases with the increasing doping concentration.And under the same doping concentration,the band gap of Mg doped 2H-CuAl_(2) is higher than that of Ca doped.The DOS(density of states)of doped 2H-CuAl_(2) is increased and then decreased with the increasing doping concentration.The doping has little effect on the conduction band and valence band near the Fermi level of 2H-CuAl_(2).