[en] In surface analysis ESCA is particularly suitable for qualitative and quantitative analysis, characterization of compounds, non-destructive in-depth analysis. ESCA ca therefore be used for the investigation of ion beam induced effects, such as selective sputtering, implantation of primary ions and surface atoms, changes in crystal structure, decomposition and formation of compounds. In the present paper the following questions will be discussed: 1) What happens during the bombardment of an oxide to metal interface. 2) Does a lower limit exist with respect to primary ion dose, current density, mass and energy for the production of ion beam induced effects. In both cases the possibility of, and time needed for, the reconstruction of the initial state seem to be important factors. (orig.)