Post acceleration of ions emitted from laser and spark - generated plasmas

Pulsed lasers at intensities of the order of 1010 W/cm2 interacting with solid matter in vacuum, produce hot plasmas at high temperatures and densities. The charge state distributions of the plasma generate a high electric field, which induces high ion acceleration along the normal to the target surface. The high yield of the emitted ions can generate a near constant current by using repetitive pulses irradiating thick targets. In order to increase ion energy, a post-acceleration system can be employed by using acceleration voltages above 10 kV. Special ion extraction methods can be employed to generate the final ion beam, which is multi-ionic and multi-energetic, due to the presence of different ion species and of different charge states. In this article four different methods of post ion acceleration, employed at the INFN-LNS of Catania, at the IPPLM of Warsaw, at the INFN of Lecce and at the LPI of Moscow, are presented, discussed and compared. All methods are able to implant ions in different substrates at different depth and at different dose-rates.