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emission of characteristic x-rays
– E.g. in a Ni Fe alloy, Ni K radiation is higher than excitation
energy for Fe K radiation
– Therefore more Fe K radiation is emitted from sample than is
generated by the incident electron beam
– Since x-rays travel further distances than electrons in matter,
atoms can fluoresce even when far removed from the
electron interaction volume. CBEMS 164 – XRD, SEM & Microanalysis: Lecture 13
! 35 X-ray Generation with Depth, (z):!
X-ray generation varies with depth as well as with atomic number.
To compare the production of x-rays at various depths, we use a relative or
normalized generated intensity, which varies with depth, called (z).
The term is called the mass depth, and normalizes for the density of different
The amount of x-ray production is a function of the amount of elastic scattering,
the initial electron-beam energy, and the energy of the x-ray line of interest.
The x-ray production varies with depth due...
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- Fall '08