COMPARATIVE INVESTIGATION ON COPPER OXIDES BY DEPTH PROFILING USING XPS, RBS AND GDOES

Depth profiling has been performed by using X-ray photoelectron spectr ometry (XPS) in combination with Ar-ion sputtering, Rutherford backsca ttering spectrometry (RES) and glow discharge optical emission spectro metry (GDOES). The data obtained by XPS have been subjected to factor analysis in order to determine the compositional layering of the coppe r oxides. This leads to two or three relevant components within the ox ide layers consisting of Cu2O or CuO dependent on the sample preparati on. GDOES measurements show sputtering profiles which are seriously in fluenced by a varying sputter rate. To ensure the results obtained so far, RES measurements of the oxide layers have been carried out in ord er to discover artefacts of the other methods used and to demonstrate the excellent suitability of RES for quantitative analysis of these la yers. Chemical analysis consisting of (1) carrier-gas fusion analysis (CGFA) and (2) selective dissolution of Cu2O/CuO allows the determinat ion of the total amount of oxygen and copper, respectively, and can se rve as a cornerstone of quantitative analysis.