Competing mechanisms for step meandering in unstable growth

Article

关键词: MOLECULAR-BEAM EPITAXY;    EHRLICH-SCHWOEBEL INSTABILITY;    VICINAL SURFACES;    FLOW GROWTH;    METAL-SURFACES;    EDGE DIFFUSION;    MORPHOLOGICAL INSTABILITY;    WAVELENGTH SELECTION;    NONLINEAR EVOLUTION;    ADATOM DIFFUSION;   

DOI  :  10.1103/PhysRevB.65.205411

来源: SCIE

【 摘 要 】

The meander instability of a vicinal surface growing under step flow conditions is studied within a solid-on-solid model. In the absence of edge diffusion the selected meander wavelength agrees quantitatively with the continuum linear stability analysis of Bales and Zangwill [Phys. Rev. B 41, 4400 (1990)]. In the presence of edge diffusion a local instability mechanism related to kink rounding barriers dominates, and the meander wavelength is set by one-dimensional nucleation. The long-time behavior of the meander amplitude differs in the two cases, and disagrees with the predictions of a nonlinear step evolution equation [O. Pierre-Louis , Phys. Rev. Lett. 80, 4221 (1998)]. The variation of the meander wavelength with the deposition flux and with the activation barriers for step adatom detachment and step crossing (the Ehrlich-Schwoebel barrier) is studied in detail. The interpretation of recent experiments on surfaces vicinal to Cu(100) [T. Maroutian , Phys. Rev. B 64, 165401 (2001)] in the light of our results yields an estimate for the kink rounding barrier at the close-packed steps.

【 授权许可】

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