Analytical Calculation of Energy Spectra of keV Light Particles Reflected from Solid Surfaces

The energy spectra of keV light particles reflected from solid surface have been calculated within the single collision approximation, taking account of the angular and lateral deviations of the indident beam caused by multiple small-angle collisions. The particle and energy reflection coefficients (R N and R E) have also been calculated as a function of the reduced energy (ε 0) in Thomas-Fermi units. It is shown that for various targets, the shape of the energy spectra at given incident and ejection angles depends only on ε 0 and that the values of R N and R E are scaled by a universal function of ε 0. Typical values of the calculated particle reflection coefficients for Au and C, together with the energy spectra for Au at normal indidence and for Fe at oblique incidence are shown to agree well with the experimental data on keV H+ obtained by the Garching group.