Molecular dynamic simulation of secondary ion emission from an Al sample bombarded with MeV heavy ions

Sputtering yields and kinetic energy distributions (KED) of Al atomic ions ejected from a pure aluminium sample under MeV silicon ion bombardment were simulated with the molecular dynamic method. Since the electronic energy loss S_e is much higher than the nuclear energy loss S_n when the incident ion energy is as high as several MeV, the S_e effect was also taken into consideration in the simulation. It was found that the simulated sputtering yield fits well with the experimental data and the electronic energy loss has a slight effect at incident ion energies higher than 4 MeV. The simulated secondary ion KED spectrum is a little lower in the peak energy and narrower in the peak width than that in the experiment.