Valence state and local atomic structure of copper in Cu-implanted silica glass

Copper implanted fused silica samples were investigated for the first time by depth-selective x-ray absorption techniques. X-ray absorption near-edge structure and extended x-ray absorption fine structure measurements were pe rformed using both x-ray fluorescence yield and conversion electron yield d etection configurations, with the aim to discriminate the contribution of t he copper ions at different depths. The copper species were found in both o xidized and metallic states. A dependence of the oxidized copper amount on the depth was detected. Compositional analyses were made by means of second ary ion mass and Rutherford backscattering spectrometries. A matrix-damage related oxidation effect on copper atoms was confirmed. (C) 2000 American I nstitute of Physics. [S0021-8979(00)03504-0].