  A discrete version of deposition-diffusion equations appropriate for
description of step flow on a vicinal surface is analyzed for a two-dimensional
grid of adsorption sites representing the stepped surface and explicitly
incorporating kinks along the step edges. Model energetics and kinetics
appropriately account for binding of adatoms at steps and kinks, distinct
terrace and edge diffusion rates, and possibly asymmetric barriers for
attachment to steps. Analysis of adatom attachment fluxes as well as limiting
values of adatom densities at step edges for non-uniform deposition scenarios
allows determination of both permeability and kinetic coefficients. Behavior of
these quantities is assessed as a function of key system parameters including
kink density, step attachment barriers, and the step edge diffusion rate.
