Single swift heavy ion irradiation setup at RBI

Deposition of large energy density at precisely defined area, by using low beam currents or even single ion irradiations, offers attractive possibilities for patterning with swift heavy ion microbeams. With a versatile ion microbeam setup, the 6 MV Tandem Van de Graaff accelerator at RBI Zagreb offers a wide range of ion species and energies that can be focused down to the submicrometer beam spot size. For the successful single ion irradiation, a reliable detection of swift heavy ion impact is necessary. This has to be accomplished both in transmission (for thin targets) as well as for the thick samples. In the case of thin targets, transmitted swift heavy ions are detected by conventional silicon particle detector, whereas for thick targets, ion impact is registered by detection of ejected secondary electrons. The current status of ion microbeam setup at RBI, Zagreb with an emphasis on low beam current operation and single ion irradiations is given. Test measurements of 10 MeV oxygen ions focused with upgraded system of magnetic quadrupole lenses in quintuplet configuration show 300 nm lateral resolution. In addition, several examples of materials patterning with our upgraded setup are presented.