Scaling Laws of the Ripple Morphology on Cu(110)

The evolution of the Cu(110) surface morphology during low temperature (180 K) ion sputtering was studied as a function of the incident ion beam angle θ by means of scanning tunneling microscopy. The morphology was dominated by a ripple structure with the wave vector parallel or perpendicular to the direction of the incident beam. The time evolution of the interface shows that the ripple wavelength increases in time following a scaling law λ∝tᶻ, with z0ex0ex=0ex0ex0.26±0.02. These results are ascribed to the effect of a Schwoebel barrier on the interlayer diffusion of the recoiling atoms produced during ion sputtering.