A routine procedure for the characterisation of polycapillary X-ray semi-lenses in parallelising mode with SEM/EDS

Abstract

The accurate knowledge of the properties of polycapillary X-ray semi-lenses has a significant influence on the quantitative results in a widespread field of applications involving microfocus X-ray beams. A routine procedure for the characterisation of a polycapillary X-ray semi-lens with a scanning electron microscope (SEM) having attached an energy dispersive spectrometer (EDS) is presented in this paper.A key issue of the procedure consists of fitting the semi-lens in front of the EDS for spectra acquisition. Relevant semi-lens parameters such as focal distance, full width at half maximum (FWHM) of the acceptance area, and transmission are determined in parallelising mode of the semi-lens. Special attention has been paid to the calculation of the transmission.

Gaining Improved Chemical Composition by Exploitation of Compton-to-Rayleigh Intensity Ratio in XRF Analysis

“…By means of a software package developed in our laboratory, XRF spectra could be calculated for the exact experimental conditions and for the elemental composition of selected reference materials measured above. The model described in detail elsewhere includes both (i) an extensive physical approach for the interaction of the X-rays with the specimen atoms , and (ii) the exact knowledge of the so-called instrumental fundamental parameters, such as the excitation X-ray tube spectra, , transmission of the X-ray polycapillary, , scattering geometry and EDS detector response. ,, Hence, reliable Compton and Rayleigh scattering peaks were calculated in the XRF spectra corresponding to the specific experimental conditions as above, their intensities divided into each other and the results “from model” also plotted in Figure . This synthetic calibration curve fits fairly well with the experimentally obtained one.…”

Atomic spectrometry update-X-ray fluorescence spectrometry

“…To advance the development of optics, as well as to determine the spectrometric properties of manufactured lenses, reliable and routine procedures were required. Such procedures for the characterisation of polycapillary X-ray half-lenses were proposed by Rackwitz et al 82 The method involved the use of an ED-SEM for the direct measurement of the lens transmission function, focal distance and full width at half maximum.…”

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

“…In this case, the excitation X‐ray spectrum is the result of the multiplication of the X‐ray tube spectrum with the transmission of the X‐ray optics. Recent works have proved that the transmission can be determined experimentally . As already mentioned previously, also in this case, the evaluation of the associated measurement uncertainties is fully disregarded.…”

“…Recent works have proved that the transmission can be determined experimentally. [2][3][4][5] As already mentioned previously, also in this case, the evaluation of the associated measurement uncertainties is fully disregarded. Because of the need of combining the X-ray tubes with such focussing polycapillary X-ray optics, X-ray tubes of the type 'side-window' only are systematically taken in consideration here.…”