Study of the sputtering of adsorbates by low energy ions (O on Ni)

Sputtering or ion impact desorption of adsorbed layers has been studied by low energy ion scattering and model calculations. For adsorption of a monolayer or less (e.g. oxygen on nickel) the desorption by ions can be readily observed by He⁺ ion scattering from the development of the adsorbate and substrate signal as a function of time. Desorption cross sections for Ne⁺ and He⁺ ions in the energy range from 500 eV to 1600 eV are given. These results are compared with the model calculations and the influence of various parameters can be studied by this comparison. The contribution of different processes to the sputtering mechanism is discussed.