The characterization of thin films and solid interfaces as well as the determina tion of concentration profiles in thin solid layers is one of the fields which re quire a rapid transfer of the results from basic research to technological applica tions and developments. It is the merit of the Dr. Wilhelm Heinrich and Else Heraeus-Stiftung to promote such a transfer by organizing high standard seminars mostly held at the "Physikzentrum" in Bad Honnef near Bonn. The present book has been stimulated by one of these seminars assembling most of the invited speakers as co-authors. The editor...