The perspective of new multi‐layer reference materials for confocal 3D micro X‐ray fluorescence spectroscopy

Abstract

Multi‐layered components are commonly used in hi‐tech branches of modern industry. This fact generates a need for suitable reference materials for experimental examination of such specimens, and it also induces the development of mathematical procedures for quantification. To reveal experimentally the chemical composition of (multi‐)layered specimens in 3D space in a non‐destructive way, a confocal 3D micro X‐ray fluorescence spectroscopy (3D μXRF) can be employed. The scope of this paper covers preparation, preliminary experimental examination and quantification of new, multi‐layer stack systems as the perspective of reference materials to be used in 3D μXRF spectroscopy. The prepared stacks consist of nine individual layers based on a low‐Z organic matrix loaded alternately with Cu2O and ZnO oxides. The stacks are characterized by the homogeneous areal distribution of inorganic fillers and the constant thickness of distinguishable layers to the extent of millimeters. A Monte Carlo (MC) simulation was used to reconstruct the chemical composition, mass density and thickness of individual layers within the stacks. Results of the simulation accurately reflected the nominal mass shares of fillers and the thickness of layers additionally determined by optical microscopy and 2D μXRF scanning. The prepared stack systems seem to be suitable materials for the validation of mathematical procedures for the quantification of multi‐layer specimens examined by depth‐sensitive X‐ray techniques. Copyright © 2012 John Wiley & Sons, Ltd.

New developments of X-ray fluorescence imaging techniques in laboratory

“…Of course, it also enables a depth elemental profiling. There are many reports of depth elemental profiling for layered materials such as paint layers [29][30][31][32][33][34][35][36][37][38][39]. The author's research group at OCU has reported a depth elemental profile for car paint chips, which have several layers depending on the type of car and manufacturing process [40].…”

Confocal micro X-ray fluorescence analysis for the non-destructive investigation of structured and inhomogeneous samples

“…Beforehand, the MC algorithm requires various parameters to be specified, like chemical composition, density, and sample size as well as experimental and fundamental parameters. Czyzycki et al successfully developed a MC simulation code (monochromatic excitation) for the determination of layer thicknesses and element concentrations of various foils and multi-layer samples by deconvolution of the depth profiles [ 61 , 62 ].…”

Depth Profiling of Element Concentrations in Stratified Materials by Confocal Microbeam X-ray Fluorescence Spectrometry with Polychromatic Excitation

“…The thicknesses of both samples were determined under optical microscope by examination of microtome cross sections of the samples. The full description of these standards was given in ref 19. Both samples were scanned in depth with the step size of 5 μm in 36 different positions (over an area of 250 × 250 μm 2 ); the average depth profile was taken for further calculations.…”