Figures 3.5 to 3.8
depict a summary of the measured secondary electron yields for different
surfaces versus primary energy. The yields increased considerably
with energy but no simple pattern was found.
Secondary electron yield for tungsten
single crystal and a tantalum foil. The angle of incidence was 82
(circles) and 60
(squares). The data for tungsten at
was taken from . The tantalum foil
surpasses clearly the tungsten singe crystal. This is probably caused
by an altered surface structure of the tantalum foil due to the rolling
process used to make the foil.
Energy dependence of ion induced secondary
electron yield for CVD diamond for three angles of incidence. The
high value for 82
and 190eV energy
per atom is probably due to the simplifications made in Equation 3.10
for the calculations. The yields were remarkably high and exceeded
unity from particle energies above 400eV per atom. The lines are shown
to guide the eye.
Secondary electron yield for AlO
and MgO coated surfaces. The values plotted represent what are believed
to be initial values as these surfaces were subject to a time dependent
secondary electron yield as described in Chapter 3.3.3.
March 2001 - Martin Wieser, Physikalisches Institut, University of Berne, Switzerland