Abstract:

Growth of Pb films on Si(111) surface at low temperatures has been found to exhibit unconventional behavior: Instead of forming three-dimensional (3D) islands of various sizes as commonly observed for nonreactive interfaces, the metal atoms arrange themselves into plateaus or islands of selective heights, with flat tops and steep edges. The extra stability of metal films with specific thickness has an electronic origin and can be explained by the ¡°quantum size effect¡± (QSE) due to electron confinement. Recent experiments also indicate that not only are these films structurally unconventional, their kinetic behavior is also fundamentally altered by quantum-size effects and does not obey traditional classical kinetic model predictions. These new experimental observations require the development of an entirely new theoretical model to describe the kinetics of the system. In this talk, I will review the experimental and theoretical studies on this interesting system. I will also discuss a theoretical model we recently developed and some large-scale quantum mechanics calculations we recently performed for understanding the kinetics of this unconventional growth behavior.
 
 
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