Physical Principles of Electron Microscopy: An Introduction to TEM ...

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Chapter 1
Figure 1-16. Photograph of Chicago STEM and (bottom-left inset) image of mercury atoms
on a thin-carbon support film. Courtesy of Dr. Albert Crewe (personal communication).
Atomic-scale resolution is also available in the conventional (fixedbeam)
TEM. A crystalline specimen is oriented so that its atomic columns lie
parallel to the incident-electron beam, and it is actually columns of atoms
that are imaged; see Fig. 1-17. It was originally thought that such images
might reveal structure within each atom, but such an interpretation is
questionable. In fact, the internal structure of the atom can be deduced by
analyzing the angular distribution of scattered charged particles (as first done
for alpha particles by Ernest Rutherford) without the need to form a direct
image.
Figure 1-17. Early atomic-resolution TEM image of a gold crystal (Hashimoto et al., 1977),
recorded at 65 nm defocus with the incident electrons parallel to the 001 axis. Courtesy
Chairperson of the Publication Committee, The Physical Society of Japan, and the authors.