TXRF technique principle

Due to the different working principles of WDXRF and EDXRF, the applications differ strongly (Table 8.43). Simultaneous WDXRF with ten channels (elements) and increased sensitivity for the low atomic number elements (e.g. a few ppm of phosphorous in a low atomic number matrix) has been used for QC of polymer granules [252], To detect elements at trace levels (ppm-ppt), generally the special XRF modes, mainly EDXRF techniques, are applied like TXRF, SR-XRF or pXRF. Detection limits with SR-XRF are now at the attogram level. 

Activation analysis is based on a principle different from that of other analytical techniques, and is subject to other types of systematic error. Although other analytical techniques can compete with NAA in terms of sensitivity, selectivity, and multi-element capability, its potential for blank-free, matrix-independent multielement determination makes it an excellent reference technique. NAA has been used for validation of XRF and TXRF. 

Total reflection X-ray fluorescence (TXRF) spectrometry is a trace elemental microanalysis technique based on conventional energy dispersive X-ray fluorescence. It has become increasingly popular in the last decade and is applied in almost every field of trace elemental analysis where low detection limits and multielement capabilities are required. Like all X-ray techniques, TXRF is nondestructive making it extremely useful and important in areas where samples are precious and/or need to be used for further characterization. New tabletop instruments make this technique affordable and more versatile as it can be used also for field research. In the semiconductor industry, TXRF is now routinely applied to scan wafers for impurities on the surface and in near-surface layers. The following article introduces the basic principle of TXRF and its instrumental features and discusses various applications of this technique. 

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