替位和间隙原子N对ZnO电子结构和光学性质的影响

Electronic structures and optical properties of substitutional and interstitial N-doped ZnO

本文采用密度泛函理论,深入研究了N作为替位和间隙原子对ZnO电子结构和光学性质的影响,结果表明:由于N在八面体间隙位置的形成能小所以更倾向于占据八面体间隙位置;N掺杂ZnO会形成p型半导体;N在间隙位置能够明显的缩小带隙宽度,可以有效的促进ZnO对光的吸收;在可见光区,处于间隙位置的N具有良好的光学吸收谱并且产生明显的红移,这与带隙的变化规律一致.

In this paper,the formation energies,electronic structures and optical properties of substitutional and interstitial N-doped ZnO were calculated by density functional theory(DFT).The results show that the N atom prefers to octahedral interstitial site because of low formation energy.The p-type ZnO is obtained by N doping,and N atom at interstitial site can narrow band gap width obviously,which will improve the solar light absorption and utilization.In the energy region of visible light,the N atom at interstitial site has a good absorption spectrum of visible light and results in redshift significantly,which is consistent with the band gap width change regulation.