SPECS PHOIBOS 100, Руководство пользователя

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Spectrometer
●
for electrons: U
0
= - 895.5 V
●
for ions: U
0
= + 895.5 V
3.6 Work Function
The basic energetic properties are shown in figure 20 for the example of the measure-
ment of photoelectrons.
Figure 20: Energy Scheme – Photoelectron Spectroscopy
The spectrometer and the sample are connected to ensure that the Fermi-energies are
at the same reference level. The binding energy of the electrons is given by
E
bin
=
h
−
E
kin
−
W f
sample
(25)
The energy E
′
kin
(see figure 20) is measured by the spectrometer and after calibrating
the work function of the spectrometer, the binding energy of the sample relative to the
Fermi level can be measured without knowing its work function because
E
kin

W f
sample
=
E '
kin

W f
spectr
(26)
Typical values of the analyzer work function are between 4 eV and 5 eV. The compensa-
tion is performed by addition through the software (see SpecsLab software manual).
For fine adjustment, use UPS mode measurement. Please check the analyzer settings in
34 PHOIBOS