TY - CONF A1 - Hertwig, Andreas A1 - Beck, Uwe A1 - Männ, Marion A1 - Weise, Matthias T1 - Certification of reference materials and validation of reference procedures: challenges on ellipsometry T2 - International Conference on Spectroscopic Ellipsoemtry T2 - International Conference on Spectroscopic Ellipsoemtry CY - Stockholm, Sweden DA - 2007-06-11 PY - 2007 AN - OPUS4-14957 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -