Removal of copper from graphene by bombardment with argon clusters: Computer experiment

The method of molecular dynamics has been used to study the bombardment of a copper film on graphene by Ar-13 clusters with a kinetic energy of 20 eV and incident angles theta = 75A degrees, 60A degrees and 45A degrees. The complete removal of copper from the graphene sheet was achieved only at the angle theta= 45A degrees. In this case, the horizontal and vertical components of the self-diffusion coefficient of copper in the film have higher values in the course of the entire bombardment. The mobility of carbon atoms and the stresses in the graphene sheet only weakly depend on the angle of incidence of clusters. The roughness of the surface of the graphene sheet subject to cleaning increases substantially only at the final stage of cleaning.