[en] As the dimensions of integrated circuits continue to shrink also the amount of tolerable contamination on Si wafer surfaces decreases. Contaminants of primary concern are transition metals and light elements like Al. Total reflection x-ray fluorescence (TXRF) spectroscopy using synchrotron radiation from the Stanford synchrotron radiation laboratory (SSRL) is one of the most powerful techniques for trace impurity analysis on Si wafer surfaces. In addition, it is among the more sensitive techniques and the only one, which is non-destructive. Upon having established a better detection sensitivity for transition elements than required by semiconductor industry, the current effort focuses on the improvement of the sensitivity for the detection and data analysis of light elements. Due to the presence of the neighboring Si signal from the substrate this can only be achieved by tuning the excitation energy below the Si-K absorption edge. For conventional TXRF systems this can be done by using a W-M fluorescence line (1.78 keV) for excitation or by employing the tunability of synchrotron radiation. However, this results in a substantial increase in background due to resonant X-ray Raman scattering. This scattering dominates the background behavior of the Al K fluorescence line, and consequently limits the achievable sensitivity for the detection of Al surface contaminants. In particular, we find that for a precise determination of the achievable sensitivity, the specific shape of the continuous Raman background must be used in the deconvolution. This data analysis opens a new perspective for conventional TXRF systems to overcome background problems in quantification and first results will be presented. (author)