Surface Scattering Experiments with Conduction Electronsshows how this process can be used to investigate surfaceprocesses of thin metal films. Since a thin film is in onedirection of a size comparable to the mean free path of theconduction electrons, such a film is both substrate andsensor and must be characterized by other surface-analyticalmethodsas demonstrated here. Also discussed is how thedc-resistivity measurement permits the study of surfaceprocesses such as adsorption, desorption, and surfacediffusion up to crystalline growth. The in situ observationof epitaxial growth is additionally shown to be possible.Thus the electronic structure of superimposed metal filmsand superlattices can be elucidated. This is an essentialtopic for all surface physicists.