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For future integrated capacitor structures, advanced new materials with a high dielectric constant (high k) and low leakage are needed. One promising material is Aluminium oxy-nitride (AlON). The thin AlON films studied in the present work were grown by reactive dc magnetron sputtering, using oxygen and nitrogen as precursor gases. The flow of these gases determines the film composition, although the relationship between flow and stoichiometry is highly nonlinear. Due to this complex processing behaviour, careful analysis of the stoichiometry of the deposited films is required. Furthermore the functionality of the films also depends both on the stoichiometry and the impurity levels, making an exact chemical analysis even more important. The composition of 200-400 nm thick AlON films were analyzed with two completely different techniques. We will present elemental depth profiles obtained by X-ray photoelectron spectroscopy (XPS) in combination with sputter sectioning and time-of-flight elastic recoil detection analysis (ToF-ERDA). By both kinds of measurements a variation in film composition through the whole film thickness was revealed. The ERDA measurements were used to calibrate the data obtained by XPS depth profiling. The results for the two analytical methods were closely matched. The methodology of the analytic techniques and both their individual and complementary benefits are discussed. |