An estimation of EDXRF spectrometer properties, based on a two‐layer composite Si‐Ge detector

Abstract

A mathematical model for the two-layer composite Si-Ge energy dispersive X-ray detector is proposed, based on analyses of radiation and electron transport in the detector, and a mathematical model of an energy dispersive X-ray fluorescent spectrometer with the detector is considered. The Monte Carlo method is applied to calculate probabilities of photon detection in different parts of the detector's response function. The composite detector with the time anti-coincidence scheme is proposed; its first layer is Si detector, and the second layer is Ge detector. It is shown that this composite detector has some advantages, such as reduced Ge photo escape peaks intensities and efficiency of detection of high energy photons similar to efficiency of Ge detector. Applying the X-ray detector for the energy dispersive X-ray fluorescent spectrometer provides for a lower background level.

2013 Atomic spectrometry update—A review of advances in X-ray fluorescence spectrometry

“…Notwithstanding the compromises, the dual detector yielded improved precision for Sn in a lead-tin solder, Cd in a RoHS polymer sample and Rh in automotive catalysts. In work also dedicated to higher X-ray stopping power and two-layer composite detectors, Portnoy and co-workers 81,82 proposed a two-layer composite silicon-germanium detector with a 0.5 mm silicon sensor on top of a 5 mm thick germanium sensor. The authors presented in detail their mathematical models for the detector response functions and also proposed a method by which the troublesome Ge K escape peaks could be compensated in a digital pulse processor.…”