Non-classical kinetics processes and morphologies in QSE driven growth in Pb/Si(1 1 1)

A novel growth low temperature morphology is observed in the growth of Pb/Si(1 1 1) related to the kinetics of Quantum Size effects. This morphology is globally observed over mesoscopic distances. Bilayer height rings nucleate first at the island perimeter which spread out towards the center. With Monte Carlo simulations the morphology is reproduced with highly anisotropic diffusion (i.e., radial diffusion out of a ring of one lattice constant is slower than azimuthal diffusion by at least 10−5 at 180 K). This shows that both kinetics and energetics are responsible for the uniform height island formation and the similar temperature “window” ∼180 K independent of the initial Si interface.