X-Ray Microanalysis in the Environmental SEM: A Challenge or a Contradiction?

Abstract

In this paper, the application of X-ray energy dispersive spectroscopy in the environmental scanning electron microscope is reviewed. Various techniques that have been used to remove the effects of the beam spreading in the gaseous environment are discussed, specifically the pressure variation techniques and the beam-stop method. The results of the application of modified versions, developed at the University of Michigan, are also presented. It is shown that quantitative analysis in the environmental SEM, operating at 30 kV, is possible at short working distances (6 mm to 7.2 mm, gas path length 1.2 mm to 2.2 mm) in the 70 to 350 Pa range.