Detection Limits and Sample Degradation
Detection limits for most trace elements are between 1012 and 1016 atoms per cubic centimetre, depending on the type of instrumentation used, the primary ion beam used and the analytical area, and other factors. Samples as small as individual pollen grains and microfossils can yield results by this technique.
The amount of surface cratering created by the process depends on the current (pulsed or continuous) and dimensions of the primary ion beam. While only charged secondary ions emitted from the material surface through the sputtering process are used to analyze the chemical composition of the material, these represent a small fraction of the particles emitted from the sample.
Read more about this topic: Secondary Ion Mass Spectrometry
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