Energy Dispersive Spectrometer (EDS)
Chemical analysis (microanalysis) in the scanning electron microscope (SEM) is
performed by measuring the energy or wavelength and intensity distribution of X-ray signal
generated by a focused electron beam on the specimen. With the attachment of the energy
dispersive spectrometer (EDS) or wavelength dispersive spectrometers (WDS), the precise
elemental composition of materials can be obtained with high spatial resolution. When we
work with bulk specimens in the SEM very precise accurate chemical analyses (relative
error 1-2%) can be obtained from larger areas of the solid (0.5-3 micrometer diameter)
using a n EDS or WDS. Bellow is a example of EDS spectrum collected in the SEM with EDS.
The spectrum shows presence of Al, Si, Ca, Mn and Fe in the steel slag phase.