ZnO(0001)Zn极性面上不同单体生长动力学特性

通过第一性原理和密度泛函方法,计算了在富锌和富氧条件下形成的Zn原子、ZnO分子、Zn3O1和Zn1O3团簇等不同单体在ZnO(0001)Zn极性面上典型的纤锌矿和闪锌矿结构沉积位的系统总能及其扩散势垒和相互作用能.结果表明,Zn1O3和Zn3O1团簇以及Zn原子单体易于获得纤锌矿结构的ZnO,而ZnO分子的稳定性较弱且易于沉积于闪锌矿位;富锌条件形成的Zn3O1团簇单体或Zn原子单体,有利于在较低温度下获得均匀结构的晶体;Zn3O1团簇单体则会形成具有一定孔洞的单一相晶体,而Zn1O3单体易形成致密的晶体;以Zn原子、Zn1O1和Zn1O3团簇为单体的沉积更易于聚集,而ZnO分子则不利于成核.

Dynamical Properties of Homoepitaxy Growth on the Zn-polar(0001)ZnO Surface by Different Monomers

In the paper,we calculated the total energies,diffusion barriers and interactive energies of different monomers deposited on the wurtzite sites(WS) and zincblende sites(ZS) by first-principle calculation and density function theory.The monomers contain Zn atom and Zn3O1 cluster formed by Zn-rich condition and ZnO molecule and Zn1O3 cluster formed by O-rich condition.The results indicated that the monomers of Zn atom,Zn3O1 and Zn1O3 cluster would easily form wurtzite structure ZnO,while ZnO molecule was inclined to deposit on the ZS and was less stable.Moreover,Zn atom and Zn3O1 cluster more easily form single phase crystal with flat and homogeneous surface and some vacancies at lower temperature.However,Zn1O3 cluster forms compact structure.Besides,Zn atom,Zn3O1 and Zn1O3 cluster would more easily nucleate,but ZnO molecule is relatively difficult to aggregate.