Ordered Monolayer Overstructures Formed on Cu Surfaces Through Segregation

The segregation kinetics of the metal dopants Sn, Sb and Ag in copper matrices were determined for three different low index orientations. In the Cu(Sn) and Cu(Sb) systems ordered submonolayer coverages were obtained following a t exp 1/2 dependence close to equilibrium values. The kinetics were found to be more complex in the case of Cu(Ag), where a relative high self interaction parameter led to a two step kinetic process. The diffusion parameters were determined in all cases by the appropriate Darken model fits and the results do suggest an orientation dependence of the diffusion coefficient D in the near surface region.