Metallography in the Scanning Transmission Electron Microscope

Abstract

The scanning transmission electron microscope (STEM) is a combination of the conventional transmission electron microscope (TEM) and scanning electron microscope (SEM) that has revolutionized the amount of information that can be obtained from a thin-foil TEM specimen. Figure 11–1(a) shows the range of signals generated when a high-energy (usually ~ 100 kV) electron beam interacts with a thin-foil specimen. Although all of these signals are theoretically accessible in the STEM, visible light and absorbed and Auger electrons are rarely sought. In practice, detectors are used to pick up the remaining signals [see Fig. 11–1(b)], as described in appropriate sections of this chapter. It will be assumed that the reader is familiar with the conventional TEM and SEM and the information that is available about them. Several standard texts describing TEM and SEM techniques are available, for example, see References 1, 2, and 3.