X-ray Detection and Analysis in XRF

The X-rays detection and analysis is usually carried out in two modes  

The system used in conventional wavelength dispersive spectrometry generally consists of an X-ray tube, an analyzing crystal, and detector (scintillation or gas flow proportional counter) as shown in Fig. 1.9. 

CrystaP/Plane 2d (A) Detection Range/Lowest-Z Detection  

The wavelength dispersive spectrometry has an overall low efficiency owing to several intensity losses through the restriction on solid angles and the low reflectivity of the analyzing crystal. Furthermore, the qualitative method of 

Soft X-rays E 1 keV) are rapidly absorbed by matter and have escape depths from a solid surface only a few pm corresponding to approximately the top thousand atomic layers of a sample. Therefore changes in peak profile, satellite peaks, etc., which are informative of chemical effects, can be used to infer chemical changes in sample surfaces. Since the air attenuation of X-ray becomes quite significant at low energies, the entire sample chamber is placed in vacuum. 

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