Specific Process Knowledge/Characterization/Element analysis: Difference between revisions
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== Energy Dispersive X-ray analysis == | == Energy Dispersive X-ray analysis == | ||
[[image:EDX-scheme.jpg|300x300px|right|thumb|X-rays are created when the high energy electrons impinge on the sample. ]] | [[image:EDX-scheme.jpg|300x300px|right|thumb|X-rays with an energy that is characteristic of the atom they are emitted from are created when the high energy electrons impinge on the sample. ]] | ||
The technique of extracting information from the X-rays generated in a sample that is irradiated with electrons is called energy dispersive X-ray analysis or EDX. (Other acronyms are Energy Dispersive x-ray Spectroscopy, EDS, or Electron Probe Microanalysis, EPMA). The energetic electrons create core level vacancies as they collide with sample atoms electrons in a multiple scattering process. To decay from this excited state photons may be emitted. Their energy is determined by the difference in energy of the shells involved. Since atomic shells are unique for every element so will be the transitions between them. Thus, every element has its own characteristic X-ray spectrum that can be used to determine the elemental composition. | The technique of extracting information from the X-rays generated in a sample that is irradiated with electrons is called energy dispersive X-ray analysis or EDX. (Other acronyms are Energy Dispersive x-ray Spectroscopy, EDS, or Electron Probe Microanalysis, EPMA). The energetic electrons create core level vacancies as they collide with sample atoms electrons in a multiple scattering process. To decay from this excited state photons may be emitted. Their energy is determined by the difference in energy of the shells involved. Since atomic shells are unique for every element so will be the transitions between them. Thus, every element has its own characteristic X-ray spectrum that can be used to determine the elemental composition. | ||