Modification of surface and bulk properties of solids by irradiation with ion beams is a widely used technique with many applications in material science. In this study, we show that nano-hillocks on CaF2 crystal surfaces can be formed by individual impact of medium energy (3 and 5 MeV) highly charged ions (Xe22+ to Xe30+) as well as swift (kinetic energies between 12 and 58 MeV) heavy xenon ions. For very slow highly charged ions the appearance of hillocks is known to be linked to a threshold in potential energy (Ep) while for swift heavy ions a minimum electronic energy loss per unit length (Se) is necessary. With our results we bridge the gap between these two extreme cases and demonstrate, that with increasing energy deposition via Se the Ep-threshold for hillock production can be lowered substantially. Surprisingly, both mechanisms of energy deposition in the target surface seem to contribute in an additive way, which can be visualized in a phase diagram. We show that the inelastic thermal spike model, originally developed to describe such material modifications for swift heavy ions, can be extended to the case where both kinetic and potential energies are deposited into the surface.

Transmission experiments o f7-200 keV H2+ ions through conical multicapillaries with inlet or outlet diameters of 4/2 gm and a length of 30 g m etched in a PC polymer are reported. The yield of the transmitted particles as a function of the capillary tilt angle was measured. The results show that for 200 keV H2+ ions the guiding effect disappears but a focusing effect is obtained with a density enhancement factor of 3.5. For 7-50 keV H2+ ions their transmitted particle curves exhibit a pair of shoulder peaks on the left-and right-hand side of the center angle 0 . As the ion energy increases, the shoulder-peak structure is found to vanish leaving one peak at 0°.