The interpretation of the broad maximum in the energy spectra of Ar+ ions scattered from the clean metal surfaces

The broad maximum in the energy spectra of Ar+ ions scattered from the clean metal surfaces to the scattering angles smaller than 90degrees is studied. Besides the Ar+ ions, other ion species (He+, N+ and Ne+) are also used as projectiles. The targets in the experiments were polycrystalline silver and copper as well as the monocrystalline nickel (110). According to the analysis of the obtained energy spectra, the maximum is interpreted as the consequence of the symmetric binary collisions between the Ar+ projectiles and the former implanted Ar atoms placed under the outermost atomic layer. This type of experiments gives a unique opportunity to study the process of low energy Ar+ ions implantation in real time, and it could be extended to other projectile-target systems of the greater technological interest.22nd Summer School and International Symposium on the Physics of Ionized Gases, Aug 23-27, 2004, Tara Natl Pk, Yugoslavi