ABSTRACT
X-ray microanalysis makes it possible for chemical analysis to be performed on biological tissue within very small and well-dened regions of specimens. All elements from Na to U can be detected while observing a specimen through an electron microscope. Using x-ray microanalysis, as little as 10−17-10−18 g of an element can be detected. It is used in such diverse scientic areas as metallurgy, physics, electronics, mineralogy, environmental pollution, geology and, lately, in pathology, zoology, biochemistry, and other biological elds. The excess energy of an electron that migrates to an inner shell to ll a newly created hole can do more than emit an x-ray. Often, instead of x-ray emission, the excess energy is transferred to a third electron from a further outer shell, which prompts its ejection. This ejected species is called an Auger electron, and the method for its analysis is known as Auger electron spectroscopy (AES).
