Creation of surface nanostructures by irradiation with slow, highly charged ions

It has recently been demonstrated that slow (upsilon << 1 a. u.) highly charged ions (HCIs) are able to generate nano-sized hillocks on cleaved CaF2(1 1 1) surfaces. The aim of the present study was to explore whether surface nanostructures can also be formed on other target materials by the impact of slow HCIs. To this purpose, we have irradiated LiF(0 0 1), diamond-like carbon (DLC) and Au(1 1 1) with slow Xe HCIs (up to charge state 44+) from the Heidelberg electron beam ion trap. After irradiation, the crystals were investigated by scanning force microscopy. Nanometric hillocks protruding from the surface were found in the topographic images for the case of Xeq+ on LiF(0 0 1) for charge states q >= 28, but not for DLC and Au(1 1 1).