Kinetic-Dynamic Properties of Different Monomers and Two-Dimensional Homoepitaxy Growth on the Zn-Polar (0001) ZnO Surface

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• 作者：Baofeng Jiang ; Chunmiao Zhang ; Changlian Jin ; Huiqiong Wang ; Xiaohang Chen ; Huahan Zhan ; Feng Huang ; Junyong Kang
• 刊名：Crystal Growth & Design
• 出版年：2012
• 出版时间：June 6, 2012
• 年：2012
• 卷：12
• 期：6
• 页码：2850-2855
• 全文大小：394K
• 年卷期：v.12,no.6(June 6, 2012)
• ISSN：1528-7505

文摘

Homoepitaxy ZnO monolayer growth was investigated from dynamics to kinetics taking ZnO molecules and Zn鈥揙 cluster monomers into account in the atomistic growth by first-principles calculations and Monte Carlo simulations and compared with experimental growth by molecular beam epitaxy. Theoretically, the ZnO molecules were found to scatter equivalently on both the wurtzite sites (WSs) and zincblende sites (ZSs) and stick even at high temperatures. The Zn₃O₁ monomers resulted in a larger island size and a higher compact degree and the growth approached to the two-dimensional mode at high temperature; the film structure finalized in the single wurtzite phase structure with more vacancies, which agreed with the in situ scanning tunnel microscopy observation for the growth in Zn-rich conditions to form Zn₃O₁ monomers. For the Zn₁O₃ monomers, the transformation from ZSs to WSs was more difficult even with temperature increase and they could locate at both WSs and ZSs, consistent with the in situ reflection high energy electron diffraction for the growth in O-rich conditions to form Zn₁O₃ monomers. Combining the advantages of both cluster monomers, a two step-growth technique was developed by alternatively supplying Zn and O. The resultant ZnO films exhibited flat texture and uniform phase structure as indicated by the atomic steps in the STM images and the streaky RHEED patterns.