Influence of quantum size effects on Pb island growth and diffusion barrier oscillations

Quantum size effects are successfully exploited in manipulating the growth of (111) oriented Pb islands on Si(111) substrate with a scanning tunneling microscope. The growth dynamics and morphology displayed can be well controlled through the quantum size effects defined by the island thicknesses and the interplay with the classical forces. The transition of growth modes from quantum to classical regime and the quantum beating in morphological dynamics are directly identified in real space and quantitatively analyzed. Atomic diffusion barriers, an important parameter in the thin film growth process, are also demonstrated to be modified by quantum size effects, and oscillate with a two-monolayer periodicity.