Sn掺杂Ga_(1.375)In_(0.625)O_3透明导电氧化物的第一性原理计算

用第一性原理计算了Sn替位Ga1.375In0.625O3化合物的Ga原子(Ga1.25In0.625Sn0.125O3)和Sn替位Ga1.375In0.625O3化合物的In原子(Ga1.375In0.5Sn0.125O3)的结构、电子能带和态密度。Ga1.25In0.625Sn0.125O3半导体材料比Ga1.375In0.5Sn0.125O3材料具有大的晶胞体积和强的Sn-O离子键。在Sn掺杂Ga1.375In0.625O3半导体中,Sn原子优先取代In原子。Sn掺杂Ga1.375In0.625O3半导体显示n型导电性,杂质能带主要由Sn 5s态组成。Ga1.375In0.5Sn0.125 O3半导体的光学带隙大于Ga1.25In0.625Sn0.125O3半导体的光学带隙。Ga1.25In0.625 Sn0.125 O3具有小的电子有效质量,Ga1.375In0.5Sn0.125O3具有多的相对电子数。

First-principles study on electronic structure and conductivity of Sn-doped Ga_(1:375)In_(0:625)O_3

The structural properties, band structures and densities of states of Sn-doped Ga1.375In0.625O3 with a Sn atom substituting for the Ga atom or a Sn atom substituting for the In atom are calculated by using the firstprinciples method. The substitution of the Sn atom for the Ga atom in Ga1.375In0.625O3（Ga1.25In0.625Sn0.125O3/has larger lattice parameters and stronger Sn–O ionic bonds than that of the substitutional doping of the Sn atom for the In atom in Ga1.375In0.625O3（Ga1.375In0.5Sn0.125O3/. Results show that the Sn atom is preferentially substituted for the In atom in Sn-doped Ga1.375In0.625O3. Sn-doped Ga1.375In0.625O3 exhibits n-type metallic conductivity,and the impurity bands are mainly provided by the Sn 5s states. The optical band gap of Ga1.375In0.5Sn0.125O3is larger than that of Ga1.25In0.625Sn0.125O3. Ga1.25In0.625Sn0.125O3 has a smaller electron effective mass and a slightly larger mobility. However, Ga1.375In0.5Sn0.125O3 has a larger relative electron number and a slightly higher conductivity.