On non-binary nature of the collisions of heavy hyperthermal particles with solid surfaces

The limits of applicability of the binary collision approximation for a des cription of scattering of atomic particles by a solid surface are discussed . The experimental data of energy losses of atoms of hyperthermal energies (HT) scattered by a solid surface were found to bring in evidence for the n on-binary nature of collisions in the hyperthermal energy region (1-30 eV). The dependence of the energy losses on the initial energy of the particles and their angles of incidence was shown to be well described by the follow ing model: the particle is being single-scattered by certain complex of sur face atoms forming an effective mass. A contribution of the non-binary coll isions to the processes of atomic and cluster sputtering is also discussed. (C) 2000 Elsevier Science B.V. All rights reserved.