EDS Data Analysis
- Practical Electron Microscopy and Database -
- An Online Book -

http://www.globalsino.com/EM/  



 
This book (Practical Electron Microscopy and Database) is a reference for TEM and SEM students, operators, engineers, technicians, managers, and researchers.
 

=================================================================================

Correct EDS data analysis is based on correct operation and data acquisition.  And then, when we work on data analysis, the following key considerations are needed:
         i) Knowledge about the sample, e.g. what is the most likely elements?
         ii) Be aware of possible elemental peaks induced by stray irradiation from the EM column and sample holder such as Fe, Cr, Ni, Cu, Zn, Al, Pt, and Mo. The stray effect is more significant if there is no stray aperture in the EM.
         iii) Confirm the elemental candidates by looking for other peaks of each element involving K, L, and M peaks
         iv) Identify the elements starting from high energy range and then low energy range because there are only few peaks at high energies
         v) Identify the shapes and energies (0-20 kV) of the proper peaks by considering the following peaks in sequence:
            v.a) K series for elements B (Z=4) to Ru (Z=44), e.g.  Kβ for Z > 16 (S)
            v.b) L series for Z ≥ 17 (Cl), e.g. Lβ for Z > 42 (Mo)
            v.c) M series for Z ≥ 47 (Ag)
         vi) Verify if there are peak overlaps. For instance, there is a peak overlap around 2.3 keV for S K 2.31 keV, Mo L 2.29 keV, and Pb M 2.35 keV and there is a peak overlap around 0.42 keV for N K 0.39 keV and Ti L 0.45 keV.
         vii) The only peaks that are statistically pronounced should be considered for elemental identification. The minimum counts (I) of the peak after background subtraction should be three times the standard deviation of the background at the peak position, i.e., I > 3(NB)1/2.
         viii) All the X-ray lines in the possible families must be marked off when an element is identified. This is extremely important for the peaks with relatively low intensities.
         ix) Artifacts such as escape and sum peaks should be marked off as each element is identified. This is more important for the high-intensity peaks.
         x) Consider what peaks may be hidden by interference.
 
 

 

=================================================================================

The book author (Yougui Liao) welcomes your comments, suggestions, and corrections, please click here for submission. If you let book author know once you have cited this book, the brief information of your publication will appear on the “Times Cited” page.