EDS / EDXRF Detector
Definition
Silicon-drift detector mounted at a fixed take-off angle to the sample that reads characteristic X-rays emitted as the primary beam ionises atoms and electrons relax. Energy resolution at the Mn K-alpha line is about 125 eV. Element range runs from boron (Z = 5) to uranium, with detection limit of roughly 0.1 weight percent under standard conditions.
- Detector type
- Silicon-drift detector
- Energy resolution
- About 125 eV at Mn K-alpha
- Element range
- Boron (Z=5) to uranium
- Detection limit
- Roughly 0.1 weight percent, standard conditions
Common questions
Why does the fixed take-off angle of the detector matter for quantitative results?+
The take-off angle affects the path length X-rays travel through the sample before reaching the detector, which influences absorption correction in quantitative analysis, so instruments are calibrated with the geometry fixed and known.
Why can this detector not reliably identify very light elements below boron?+
Elements lighter than boron emit X-rays of very low energy that are strongly absorbed before reaching the detector window, falling below the practical detection range of standard silicon-drift EDS/EDXRF systems.
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