Diffusion of a single Cu adatom on low-index Cu surfaces with different morphologies (with and without the presence of other Cu adatoms as well as near and over stepped surfaces) is studied using the embedded-atom method and a molecular static simulation. Migration energies of a Cu adatom in the presence of other Cu adatoms which are relevant in computer simulations of island growth are calculated. We have also calculated the formation and migration energies of an adatom and a vacancy in different layers as well as formation energies of steps on various Cu surfaces. Step-step interaction is shown to be repulsive and consistent with elasticity theory. Our calculations predict a lower activation energy for diffusion of a vacancy than of an adatom for all three Cu surfaces.

We present a class of models that describe self-diffusion on FCC(001) metal substrates within a common framework. The models are tested for Cu(001), Ag(001), Au(001), Ni(001) and Pd(001), and found to apply well for all of them. For each of these metals the models can be used to estimate the activation energy of any diffusion process using a few basic parameters which may be obtained from experiments, ab-initio or semiempirical calculations. To demonstrate the approach, the parameters of the models are optimized to describe self-diffusion on the (001) surface, by comparing the energy barriers to a full set of barriers obtained from semi-empirical potentials via the embedded atom method (EAM). It is found that these models with at most four parameters, provide a good description of the full landscape of hopping energy barriers on FCC(001) surfaces. The main features of the diffusion processes revealed by EAM calculations are quantitatively reproducible by the models.

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