Energy loss of ions in solids, the ion charge dependence

E. D. CANTERO; M. BEHAR; R. C. FADANELLI; G. LANTSCHNER; N. R. ARISTA; C. C. MONTANARI; J. E. MIRAGLIA

Caen

Congreso; 22nd International Symposium on Ion Atom Collisions; 2011

Universite de Caen Basse-Normandie

We present a combined theoretical-experimental study of the energy loss of ions in solids We choosed Zn as a target due to its technological applications and scarce data, and varied the ions from He to C [1]. The covered energy region is (50-1000) keV/amu which includes the maximum of the stopping power. The energy loss determinations were done by the Rutherford backscattering technique at the 3 MV Tandetron of the Instituto de Fisica  of the Universidade Federal de Rio Grande do Sul in Brazil. The Zn target in films composed by Au/Zn/Au deposited on Si wafers were produced at the Centro Atómico Bariloche in Argentina.. The theoretical description is performed using different models for valence and inner-shell electrons: a non-perturbative scattering model using the Extended FriedelSum Rule approach [2], and the Shellwise Local Plasma Approximation (SLPA). The SLPA treats each entire electron shell as a plasma of Fermi velocity determined by the local electronic density (independent shell approximation) [3], and taking into account the energy threshold. The projectile electronic structure is also taken into account in a very detailed way. This combined theoretical description explained well the energy loss of ions in Zn, with C being the highest limit for the SLPA which is a perturbative model. On the other side, the comparisson of the experimental measurements with the known SRIM calculations shows the good performance of this semiempirical model too.