Behavior of the continuous X-ray background in grazing-exit electron probe X-ray microanalysis

The energy distribution of the background radiation originating from two kinds of substrate materials has been studied using Electron Probe X-Ray Microanalysis (EPMA) at grazing-exit angles. The different behavior between tendencies of background reduction for the silicon and the gold substrates at the grazing exit angle is explained using a critical energy concept. It is also shown experimentally that a gold substrate results in a lower background intensity than a silicon substrate in the energy region 5-7 keV, while on the other hand, for elements with X-ray lines of 2-3 keV, it is advantageous to perform the analysis when such elements are deposited on the silicon substrate.