Total reflection x-ray fluorescence analysis - a review

Total reflection x-ray fluorescence analysis (TXRF) is a special energy-dispersive x-ray analytical technique extending XRF down to the ultra trace element range. Detection limits of picograms or nanograms per gram levels are reached with x-ray tube excitation. Using synchrotron radiation as excitation source, femtogram levels are detectable, particularly important for Si wafer surface analysis. TXRF is specially suited for applications in which only a very small amount of sample is available, as only a few micrograms are required for the analysis. In this review, an overview of theoretical principles, advantages, instrumentation, quantification and application is given. Chemical analysis as well as surface analysis including depth profiling and thin-film characterization is described. Special research results on extension to low-Z elements, excitation with synchrotron radiation and x-ray absorption spectroscopy (XAS) for chemical speciation at trace levels are reviewed. Copyright (C) 2007 John Wiley & Sons, Ltd.