Artifacts in Transmission Electron Microscopy - Sample Preparation Topic for Transmission Electron Microscopy - page 125

Chapter 6
Artifacts in Transmission Electron Microscopy
1 Introduction
An artifact is damage caused by a preparation technique and can easily be
confused with the sample's microstructure. Artifacts can be due to mechanical,
chemical, ionic, or physical action. During TEM observation, especially in a
TEM/STEM, other artifacts may be produced due to irradiation under the electron
beam.
Therefore, there are two families of artifacts: those formed during the prelim-
inary preparation steps and sample thinning and those formed under the effect of
the electron beam during observation. Materials will be more or less sensitive to
the formation of artifacts depending on their type and the nature of the chemical
bonds.
2 Preparation-Induced Artifacts
Included among the possible artifacts are primary damage, formed by the prepara-
tion techniques, and secondary thermal damage, caused by a rise in the temperature
during preparation or during observation under the electron beam. Table 6.1 shows
all of the possible artifacts.
The artifacts and secondary thermal damage have been classified based on either
the type of action (mechanical, ionic, chemical, and physical) involved in the prepa-
ration of the thin slices or their formation during the electronic radiation in the
microscope.
The definition of each artifact is provided, as well as the preparation techniques
from which they may be derived.
Lastly, this chapter presents illustrations of the artifacts most commonly encoun-
tered in the mechanical, ionic, chemical, and physical thinning techniques. It also
provides illustrations of artifacts derived from the combination of several techniques
in the fields of solid-state physics and biology.