Defect Mediated Desorption of the KBr(001) Surface Induced by Single Highly Charged Ion Impact

The formation of nanometer sized monoatomic deep pits on the KBr (001) surface induced by individual impacts of slow (1keV/amu) highly charged Xe ions has been investigated. The volume of the pits have been determined by atomic force microscopy and show a strong dependence on the ions potential energy. The imaging of single ion impact sites allowed us to determine total potential sputter yields from atomically flat (001) terraces. From the dependence of the pit formation ability on the ions initial charge state and the comparison of low and high fluence irradiations we found evidence that defect agglomeration into complex defect centers plays a major role in the desorption process induced by the potential energy.