SPM observation of nano-dots induced by slow highly charged ions

We have observed nano-dots on a highly oriented pyrolytic graphite (HOPG) surface produced by highly charged ion impacts with a scanning probe microscope. In order to clarify the role of potential and kinetic energies in surface modification, we have measured the kinetic energy and incident ion charge dependences of the dot size. The results showed that the potential energy or the incident ion charge has strong influence on the surface modification rather than the kinetic energy.