Cu-Fe共掺杂ZnO电子结构与光学性质的第一性原理计算研究

基于密度泛函理论的第一性原理平面波超软赝势方法,计算了本征ZnO,Cu、Fe单掺杂和Cu-Fe共掺杂ZnO的电子结构和光学性质.计算结果显示:Cu掺杂属于p型掺杂,Fe掺杂属于n型掺杂,单掺杂时Cu-3d态电子和Fe-3d态电子均在禁带形成杂质能级,从而提高ZnO的载流子浓度,改善ZnO的导电性能,而Cu-Fe共掺杂时ZnO半导体进入简并态,呈现金属特性.掺杂后的ZnO介电函数虚部变化主要集中在低能量区域,光谱吸收系数及反射率曲线发生红移,其中本征ZnO对太阳光谱有较好的透射性,Fe单掺杂和Cu-Fe共掺杂ZnO对可见光谱有相似的吸收效果,而Fe单掺杂ZnO对近紫外区域的光谱透射率更小,适用于制备防紫外线薄膜.

The electronic structure and optical properties of Cu-Fe codoped ZnO based on first-principles

By using the first-principles plane-wave ultrasoft pseudopotential method based on the density functional theory,we calculated the electronic structures and optical properties of intrinsic ZnO, Cu doped, Fe doped and Cu-Fe co-doped ZnO compounds. The results show that the Cu doped ZnO is P type doping,and Fe doped ZnO is N type doping. In the case of single doping, Cu-3d and Fe-3d state electrons increase the carrier concentration of ZnO and improve the conductivity of ZnO because of the formation of impurity levels in the forbidden band. The ZnO semiconductor enters the degenerate state and exhibits metallic properties in the case of Cu-Fe co-doped. The imaginary part of ZnO dielectric function changes mainly in the low energy region, the absorption coefficient and reflectance curve of the spectrum are red-shifted after doping.Among them, intrinsic ZnO has better transmittance to the solar spectrum, Fe single-doped and Cu-Fe co-doped ZnO have similar absorption effect to the visible spectrum, while Fe single-doped ZnO has lower spectral transmittance to the near-ultraviolet region, which is suitable for preparing anti-ultraviolet films.