SEM EDS

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"Energy-dispersive X-ray spectroscopy (EDS, EDX, or XEDS)"

List of EDS manufacturers:

Typical systme:

    • Thin window (Be, C, B)
    • SiLi crystal
    • FET pre-amplifier
    • Vacuum
    • Cold finger
    • Pre-amplifier
    • Amplifier
    • MDA electronics (“multi channel analyzer”)

Detector

Styles

    • Si-Li
    • Silicon Drift Detector (SDD)

Si-Li

Operates at LN2 temps. If operated at room temp it will be destroyed

SDD

"SDD detectors operate at a few tens of degrees below zero"

Window

Styles [epmalab]:

    • Be foil
    • Supported window
    • Windowless

Be foil

"The most common EDS detector window has been made of Be foil ~7.6 um (0.3 mil) thick. It allows good transmission of X-rays above ~ 1 keV. It is strong enough to withstand venting to atmospheric pressure, and opaque to optical photons." [epmalab]

Supported window

"For transmission of light element X-rays (<1 keV), windows ~0.25 um thick of BN, SiN, diamond or polymer are used. They must use supporting grids to withstand pressure differentials; the grid (e.g., Si or Ni) takes up about 15% of the area, but thin enough that low energy X-rays pass through." [epmalab]

Ultra Thin Window (UTW)

made of:

    • Polymide ref]
    • "poly-vinyl formal (FORMVAR), butvar, parylene, kevlar, polypropylene, lexan or polyimide" ref]

Windowless

"no film, and there is a turret that allows swapping with a Be window. Difficult to use as oil or ice can coat the detector surface" [epmalab]

Gamma Spectacular

[1]]

How hard would it be to use this as EDS controller?

Model comparison

Image Vendor Model Year Features List price Ask price Manual Schem SW
EDAX Genesis Spectrum 2006 Yes] [Yes] | ]


References

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