摘要
利用第一性原理,研究了ZnO晶体Al杂质与Zn间隙共存的复合缺陷(AlZnZni)电子结构和光学性质。计算结果显示,AlZnZni复合缺陷的形成能为-3.180 e V,较低的形成能表明这种缺陷容易形成;复合缺陷使ZnO晶体的能带整体下移,带隙减小,价带区域展宽;电子能带结构的变化对ZnO的光学性质在低能产生了重要影响,主要表现在:介电函数虚部往低能方向移动且强度显著增强,使得ZnO表现出简并半导体的特性;复合缺陷导致ZnO晶体光学吸收边缘产生了红移,可见光区的吸收系数增大,透过率降低。
The electronic structure and optical properties of composite defect in ZnO crystals were study by first principles. The calculation results show that the formation energy of the AlZnZnicomposite defect is-3. 180 e V. The structure is more in favor of the formation of AlZnZnicomposite defect. The band of Al Zn,Zni co-existent ZnO move down,the band gap decreases and the valence band broaden. The change of the electronic band structure has important influence on the optical properties of ZnO in low energy range as follows： the imaginary part of the dielectric function move in the direction of low energy range,and the strength of dielectric function show a great enhancement,which present the characteristics of degenerate semiconductor for the AlZn,Znico-existent ZnO. Absorption edge occur red-shift,and the absorption coefficient increases in the visible light region.
出处
《人工晶体学报》
EI
CAS
CSCD
北大核心
2016年第6期1508-1513,共6页
Journal of Synthetic Crystals
基金
四川省科技厅应用基础项目(2014JY0133)
中国科学院太阳活动重点实验室开放课题(KLSA201514)
