Quantitative X-Ray Microanalysis of Bulk Materials at High Energy (60-400 keV)

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The objective of this project consists of elaborating a simple, reliable and efficient tool for quantitative x-ray microanalysis of bulk specimen in the transmission electron microscope (TEM) for electron energies from 60 to 400 keV. Such tools do not exist presently. In 2009, Bruker introduced the first Silicon Drift Detector (SDD) that can be installed in a TEM that provides, at least, a photon count rate of 500 000 counts/s with energy resolution similar to Si(Li) EDS detectors. The first SDD detector was installed to the Field Emission Scanning Transmission Electron Microscope (FE-STEM) Hitachi HD-2700 of Hydro-Québec Research Center. It is now possible to acquire x-ray spectra of bulk specimen in the TEM for electron energy above 60 keV. However, quantitative x-ray microanalysis of x-ray spectra acquired for electron energies above 60 keV is not possible because the quantitative models that already exist for bulk specimen were developed for electron beam energy below 30 keV, the electron energies used by the electron microprobe and the SEM. This collaborative research grant is to develop, in collaboration with Bruker and Hydro-Québec, a method to perform quantitative x-ray microanalysis of bulk specimen in the 60 - 400 keV range. It is expected that quantitative x-ray microanalysis of bulk specimen in the TEM will lower the detection limit of trace elements. Finally, comparisons will be performed for the analysis of bulk materials between 30 and 200 keV in order to show the advantages and limitations of these energies for quantitative x-ray microanalysis of bulk specimens.