UNIVERSITY OF BUCHAREST
FACULTY OF PHYSICS

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2024-11-22 2:03
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Conference: Bucharest University Faculty of Physics 2018 Meeting


Section: Optics, Spectroscopy, Plasma and Lasers


Title:
Standardless / one standard calibration methods for microbeam X-ray fluorescence instrument


Authors:
Mihail LUNGU (1), Cosmin DOBREA (1), Ioana POROSNICU (1,2), Ion TISEANU (1)


*
Affiliation:
1) National Institute for Laser, Plasma and Radiation Physics, 077125 Bucharest, Romania;

2) University of Bucharest, Faculty of Physics, Atomistilor Str. 405, 077125, Magurele, Romania;


E-mail
mihail.lungu@inflpr.ro


Keywords:
XRF, fundamental parameters, spectroscopy, alloys, multilayers;


Abstract:
X-ray fluorescence (XRF) methods are widely applied for qualitative and quantitative investigations of elemental composition and single and multi-layer thickness determination. The accuracy of the quantitative analysis is strongly dependent on the calibration techniques used. In this study an in-house build microbeam XRF is the main non-destructive and sample safe instrument that integrates specially optimized X-ray optics, hence providing a high resolution for experiments [*]. Currently, the absolute elemental composition analysis is performed with calibration curves based on multiple standards. For the coating thickness measurement, one uses multiple samples with known layers thickness. In specific cases the calibration curves were based on a combination of one/few standard samples and additional numerically simulated measurements by Monte Carlo radiation transport codes. Recently, we extended our calibration techniques based on a Fundamental Parameters software package (XRS-FP) with the additional integrated Spectra-X that converts measured elemental peak intensities to elemental concentrations or film thicknesses. Within the XRS-FP & Spectra-X modules the processing of the XRF spectra was significantly simplified. Several steps in the typical processing of an XRF spectrum by means of XRS-FP software are presented, such as spectrum smoothing, sum-peak removal, background removal and intensity extraction. Automated and manual modes were calibrated according to the standard samples availability such as: standardless, one standard or multiple standards. One especially outlines the differences between standardless and standard based measurements. Finally, one exemplifies the applicability of the analysis for couple of relevant alloys and multilayer configuration samples.


References:

[*] Ion Tiseanu et al. X-ray microbeam transmission/fluorescence method for non-destructive characterization of tungsten coated carbon materials, https://www.sciencedirect.com/journal/surface-and-coatings-technology ,Volume 205, Supplement 2, Pages S1-S608, (2011);