Scaling behavior of island density in submonolayer growth of CaF2 on vicinal Si(1Â 1Â 1)

We have studied the scaling behavior of two-dimensional island density during submonolayer growth of CaF2 on vicinal Si(1 1 1) surfaces using scanning tunneling microscopy. We have analyzed the morphology of the Si(1 1 1) surfaces where CaF2 partial monolayers with coverages of about 0.1 monolayer are deposited at ∼600 °C. The number density of terrace nucleated islands increases with substrate terrace width l as ∼l4 in a low island density regime. This scaling behavior is consistent with predictions for the case of the irreversible growth of islands.