different types of interactions appear:
No energy is transferred from the electron to the sample.
The electron either passes without any interaction (direct beam) or is scattered
by the electrostatic attraction of the positive potential inside the electron cloud. The arising signals
are mainly exploited in TEM and electron
Energy is transferred from
electrons to the sample producing secondary
electrons, phonons, UV quanta or cathodo-luminescence. Ionization of atoms by removing inner
shell electrons leads to the emission of X-rays or Auger electrons. These
signals are used in analytical electron microscopy.
A script giving an introduction can be downloaded here: interactions.