Do elemental peaks on SEM-EDS spectra relate to concentration

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Analyzing crystals using SEM-EDS for calcium concentration can yield variable results, as indicated by differing calcium peak heights in the EDS spectrum. Achieving accurate quantitative results in EDS analysis is challenging due to factors such as signal-to-noise ratio, sampling rate, and the need for ZAF correction factors. Using well-characterized standards is crucial for reliable quantification. Typically, results may vary significantly, often exceeding a 20% accuracy threshold, highlighting the complexities involved in EDS spectrum analysis.
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Hello,

I recently did an experiment where I examined and analyzed crystals using SEM-EDS. One of the major parts of my experiment was to determine the concentration of a certain element (calcium) in the different crystal samples. I noticed that some calcium peaks were higher than others. Does this relate to concentration at all?

Thanks
 
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EDS spectrum analysis can be notoriously difficult when you want quantitative results. Do a search on 'quantitative EDS' - lots of things to learn about.

The short of it is that you typically want to use a spectrum with good signal to noise ratio, collected with a sampling rate that minimizes various sampling errors, and quantitate the spectrum using ZAF correction factors using standards whose compositions are accurately determined using other techniques.

Generally speaking, it's very difficult to get results within 20% accuracy, and often the results can be off by much larger factors.
 
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