Step-edge-induced nucleation plays a key role in controlling the growth of novel nanostructures and low-dimensional mat erials. However, it is difficult to experimentally determine the step edge structures of complex ...Step-edge-induced nucleation plays a key role in controlling the growth of novel nanostructures and low-dimensional mat erials. However, it is difficult to experimentally determine the step edge structures of complex metal oxides. In this work, we present a detailed theoretical study of the stability of stoichiometTic steps on sapphire(OOOl). Based on first-principles calculations and excess charge computation by Finnis1 approach, a pair of non-polar step edges are determined to be the most stable. By studying the adsorption characteristics of ZnO and combining previous works, we successfully explained how growth temperature and deposition rate affect the in-plane orientation of ZnO grown on sapphire(OOOl). The knowledge on the step edge structures and nucleation patterns would benefit the study on step-edge-guided nanostruc ture grow th.展开更多
基金the National Natural Science Foundation of China under Grant Nos. 11274179 and 11574157the National 973 Projects of China under Grant No. 2012CB921900.
文摘Step-edge-induced nucleation plays a key role in controlling the growth of novel nanostructures and low-dimensional mat erials. However, it is difficult to experimentally determine the step edge structures of complex metal oxides. In this work, we present a detailed theoretical study of the stability of stoichiometTic steps on sapphire(OOOl). Based on first-principles calculations and excess charge computation by Finnis1 approach, a pair of non-polar step edges are determined to be the most stable. By studying the adsorption characteristics of ZnO and combining previous works, we successfully explained how growth temperature and deposition rate affect the in-plane orientation of ZnO grown on sapphire(OOOl). The knowledge on the step edge structures and nucleation patterns would benefit the study on step-edge-guided nanostruc ture grow th.
