Step edge barriers on GaAs(001)

We investigate the growth kinetics on vicinal GaAs(001) surfaces by making detailed comparisons between reflection high--energy electron--diffraction specular intensity measured near in--phase diffraction conditions and the surface step density obtained from simulations of a solid--on--solid model. Only by including a barrier to interlayer transport and a short--range incorporation process of freshly--deposited atoms can the simulations be brought into agreement with the measurements both during growth and during post--growth equilibration of the surface.