采用平面波超软赝势密度泛函理论计算方法研究了p型Cu掺杂的纤锌矿结构氧化物ZnO的电子结构,在此基础上分析了其电输运性能。计算结果表明,Cu掺杂ZnO氧化物具有0.6 eV的直接带隙,且为p型半导体,在导带和价带中都出现了由Cu电子能级形成的能带,体系费米能级附近的能带主要由Cu p态、Cu d态和O p态电子构成,且他们之间存在着强相互作用。电输运性能分析结果表明,Cu掺杂的ZnO氧化物价带中的载流子有效质量较大,导带中的载流子有效质量较小;其载流子输运主要由Cu p态、Cu d态、O p态电子完成,且需要载流子(空穴和电子)跃迁的能隙宽度较未掺杂的ZnO氧化物减小。
The electronic states and electrical transport properties of the Cu doped wurrite type ZnO were investigated by the plane wave ultro-soft seudo-potentials based on the density functional theory calculations.The calculational results show that the Cu doped wurrite type ZnO has approximately 0.6 eV direct band gap and it is p type semiconductor,there are newly formed bands within the valence bands and conducting bands that are from the electons of dopant Cu.The bands near Fermi level are formed by the Cu p,Cu d as well as the O p state electrons and there are high interactions between them.The analyzing results of the electrical transport properties show that carriers within the valence bands have heavy effective mass and the carriers within the conduction bands have light effective mass for the Cu doped wurrite type ZnO.The carrier transport process is estimated to be accomplished by the Cu p,Cu d as well as the O p state electrons.Furthermore,the energy gap for electron or hole carriers to surpass is narrowed by Cu doping for Zn.