Latent tracks in CaF2 studied with atomic force microscopy in air and in vacuum

Comparative studies of height of surface tracks employing different modes of imaging by atomic force microscopy in air and vacuum have been performed. The surface tracks were induced on CaF2 by 11.1 MeV u−1 bismuth ions impacting at normal incidence. Different imaging modes, like tapping in air and contact and non-contact in vacuum yield the same measured hillock heights, whereas contact mode in air yields substantially smaller heights. This can be explained by different elasticity modules of the hillocks and the non-irradiated surface. AFM tapping mode is adequate to study the topography of irradiated CaF2 targets under ambient conditions.