Atomically resolved scanning tunnelling microscopic images were obtained of the nanostructures on various types of surface bombarded with highly charged ions. In the case of a TiO2(110) surface, a typical nanostructure induced by a single I51+ highly charged ion impact, the height (~1nm) was higher than the atomic step of the TiO2(110)-(1 x 1) surface (~0.3nm) and the depth reached at least 1.5nm.

Observation of HCl-Induced Nanostructures with a Scanning Probe Microscope. Tona, M., Watanabe, H., Takahashi, S., Fujita, Y., Abe, T., Jian, S., Nakamura, N., Yoshiyasu, N., Yamada, C., Sakurai, M., Ohtani, S.: Journal of Physics - Conference Series, 2007, 58, 331-4