摘要
采用密度泛函理论研究了Ⅲ族元素掺杂对SnO2电子结构及电学性能的影响.态密度分析结果表明,以替代位存在的Ⅲ族杂质均使SnO2的费米能级明显向低能态方向移动,使得价带顶不完全填满,因此在SnO2中均充当受主作用.部分态密度分析结果表明,相对于掺Al的SnO2,Ⅲ族元素中的Ga及In对费米能级附近态密度贡献较大,其主要贡献来自Ga3d态或In4d态,这预示着在SnO2中掺Ga或In能实现更好的p型掺杂效果.电离能计算结果进一步表明,在Al,Ga及In三种元素中,替位In有最小的电离能(0.06eV),这说明其在SnO2中能形成最浅的受主能级,因而在同等掺杂情况下,可引入最高浓度的空穴,从而实现最佳的p型掺杂效果.
The electronic structures of SnO2 doped by Al, Ga and In were examined using density functional theory. Density of states （DOSs） calculation showed that the Fermi levels of all Ⅲ-family doped SnO2 systems shift to lower energy and therefore a partially occupied valence band was formed near the valence maxima, which indicates that substitional Ⅲ soup atoms act as acceptors in SnO2. Partial DOSs indicates that compared with substitional Al, substitional Ga or substitional In contribute much more because of the d states, Ga3d or In4d, which suggests that Ga and In is better than Al for p-type doping of SnO2. Ionization energy calculation further indicates that, of the substitional In, Ga and Al, substitional In has the smallest ionization energy of 0.06 eV, which means that substitional In gives the shallowest acceptor level in SnO2, and thus the highest hole concentration at the same doping concentrations.
出处
《物理学报》
SCIE
EI
CAS
CSCD
北大核心
2007年第4期2388-2392,共5页
Acta Physica Sinica
基金
国家自然科学基金(批准号:60576063)
教育部博士点基金(批准号:20050335036)资助的课题.~~
关键词
密度泛函理论
SNO2
Ⅲ族元素掺杂
电子结构
density functional theory, SnO2, Ⅲ-family element doped, electronic structure
