Cluster ion beam irradiation at low energy and surface pattern formation

Ion beam sputtering is a solid-surface nanostructuring procedure. In this work, we are interested in studying the formation of surface patterns during this process. To do this, a Cobalt metal surface is bombarded with clusters at oblique incidence. Cluster bombardment is used since clusters accentuate the effect of surface ripple formation. Two processes explain the effect of pattern formation at the collisional level when diffusion phenomena can be neglected, namely sputtering and atomic redistribution. In the present work, the effect of the energy of the cluster atoms and the surface orientation on the above processes and, therefore, on the surface pattern formation, are analyzed. In the case of energy, it is found that this represents an additional excitation to the formation of patterns. Therefore, if it increases, the surface irregularities increase in turn. However, the specific weight of the processes that support the process is maintained. On the contrary, the crystallographic structure can affect this specific weight. In fact, the formation of patterns on the (100) surface is justified by sputtering regardless of the angle of incidence.