On the Sampling Depth of Total Electron Yield (Tey) Measurements

Extract

Photoabsorption of x-rays in solids causes primary and secondary photo and Auger electrons. The latter are from self absorption of characteristic radiations which have been produced in the solid by radiative de-excitation of photoionized atoms. Whereas the energy of the electrons at the origin is described by discrete values of a few eV up to nearly the energy of the photoabsorbed photons, we observe after the escape of the electrons from the solid a continuous energy distribution with a superposition of the original line spectrum. This is explained by inelastic collisions of the electrons in the course of their migration through the solid and the subsequent loss of kinetic energy. Since the electron range decreases with decreasing kinetic energy, only a relatively small amount of electrons is able to reach the surface and to escape from there.