Calculation of X‐ray tube spectra by means of photon generation yields and a modified Kramers background for side‐window X‐ray tubes

Abstract

Popular X‐ray tube models available in the literature, i.e. ‘Pella’, ‘Ebel’, and ‘Finkelshtein and Pavlova’, are systematically evaluated with the focus on the estimation of the associated uncertainties. Also taken in consideration and compared is our recent semi‐empirical own approach already employed in our lab. This has been working for the common target elements rhodium, molybdenum and tungsten and was further extended in the present work for the target elements copper, chromium and vanadium. By using a modern scanning electron microscope/energy dispersive spectroscopy (SEM/EDS) system this time, higher performances such as stability of the beam current and especially the better energy resolution of the EDS have enabled the reliable extension of our own X‐ray tube spectrum approach into the low‐energy range, due to increasing interest. Hence, also the more challenging X‐ray lines of copper, chromium and vanadium L‐series lying in the energy range below 1–2 keV are included into the model. Such low‐energy L‐lines or, e.g. M‐lines of tungsten, are not treated explicitly by the other existing popular algorithms for the nowadays widely used geometries of side‐window tubes, offering a unique virtue to our present, modern approach. With our own model, a measurement uncertainty of the X‐ray tube spectra (considering the uncertainties associated with the SEM beam current, the detector acceptance solid angle and efficiency of the spectrometer) within 15% has been estimated. The validation of the approach is demonstrated with metrological measurements with a calibrated SEM/EDS system geometrically configured as a side‐window X‐ray tube. Copyright © 2012 John Wiley & Sons, Ltd.

Inspection of morphology and elemental imaging of single nanoparticles by high‐resolution SEM/EDX in transmission mode

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2013 Atomic spectrometry update—A review of advances in X-ray fluorescence spectrometry

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Performance of μ-XRF with SEM/EDS for trace analysis on the example of RoHS relevant elements – measurement, optimisation and prediction of the detection limits

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