Omicron CN 10 V020 pages

MBE PRO 753-V01/Oct10
CN 10 - Charge Neutraliser
The CN 10 is specifically
designed to provide
charge compensation
for analysis of insulating or semiconducting
materials during
photon or ion bombardment.
The CN 10 is an electron source for
charge neutralisation. The low energy
spread of the BaO filament ensures
ultimate XPS resolution on insulators.
It is optimised for high beam currents
down to lowest energies (10 eV and
below).
X-ray Photoelectron Spectroscopy (XPS)
is ideal for investigating insulating materials
such as polymers, ceramics and adhesives etc.
However, the XPS technique leads to a depletion
of electrons, which are not replaced in insulators, leading to a change in surface potential.
The phenomenon of surface charging can be a
particular problem during monochromated XPS,
where a dynamic equilibrium is not established
between the photoelectrons leaving the sample
and the electrons delivered from the vacuum
or sample bulk. A variable surface charge can
cause a decrease in analyser energy resolution
due to peak broadening and the shifting of the
measured photoelectron peaks. This in turn will
reduce the elemental, chemical state and surface
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bonding information obtainable from a sample. In
order to achieve optimal sensitivity and resolution
any surface charging effects must be minimised.
The CN 10 is supplied as standard with an activated and tested low work function Barium Oxide
emitter, able to supply a current density of up to
400 nAmm2 and a KE of 0 ...16 eV. The creation of
an high electron flux allows the operator to selectively tune out varying degrees of localised charging ensuring optimum XPS energy resolution. In
addition the CN 10 has been designed to operate
as part of a ‘Dual-Beam’ charge neutralisation
scheme in combination with the FIG 05 floating
ion column. The combination of both ‘slow’ electrons (CN 10) and ions (FIG 05) allows even the
most inhomogeneous ceramic compounds to be
fully characterised. On samples such as bulk PET
FWHM have been measured below 0.71 eV.
UHV System integration
The CN 10 is available either as part of a fully
integrated XPS solution or as a stand-alone unit,
flexibly designed for integration into any system
with a suitable port. The latest version of