SIMULATION OF LOW-ENERGY HCI-SOLID INTERACTION

The interaction of low-energy highly charged Xe-q+ ions (q = 1-44) with a diamond crystal has been investigated, using the time-evolution binary collision simulation code DYACOCT. The nuclear interaction between a charged particle and a neutral atom is calculated by the binary collision approximation, and the Coulomb interaction between charged particles is calculated by the molecular dynamics technique. It is found that the screening shift is very important in the decay dynamics of electrons captured into highly exited states in an early stage of the collision process. Some of the captured electrons are stripped off due to the peeling-off process before the intra-Auger decay becomes dominant when 10 keV Xe-q+ (q greater than or equal to 36) ions approach a diamond surface. The slow highly charged Xe-q+ ions are almost neutralized before entering diamond. The sputtering yield due to a 10 keV Xe-q+ (q greater than or equal to 18) ion is about ten times larger than that due to a singly charged Xe+ ion and the charge fraction of sputtered particles is about 15%.