Design
and
manufacture
Great care has been taken with the design and manufacture of
the cell in order to
repeatedly
obtain the same
characteristics
and to achieve excellent stability:
– the metal parts are made of stainless
steel,
– the filament holder is made of
machined aluminium,
– there is an integral
amplifier
.
The cell assembly is
composed of:
–
a
vacuum
chamber
or deflection
chamber
,
– an optic holder
flange,
–
a permanent magnet,
– an
amplifier
.
•
The vacuum
chamber:
The analysis cell vacuum
chamber
is made of light alloy.
It
is
hollow with
a rectangular opening
into which the
electrodes,
(that are installed on the «optics holder» flange) are
placed.
•
The optics holder
flange:
The optics holder flange supports all the electrodes and
electrical
connections in the cell. They
include:
– the sealed power supply socket, mounted on
a
metal
gasket,
– the amplifier, mounted on an elastomer
gasket,
vthe supporting block which screens the target and on which
the
source of ions is
mounted,
– the source of ions, which is made up of 2
par
ts:
• a
filament
holder
,
•
an ionization
chamber
with
a
stainless steel electron
collector
and
a
mass ion emitter
.
The filament holder
mechanically
positions the tungsten filament
with respect to the ionization
chamber
.
The electron collector and the filament have been
designed
and positioned so that the
temperature
of the electron
collector
stabilizes at
400°C
under
bombardment
and
radiation
from
the
filament. The cell is thus
rendered
immune to
contamination
from
the pieces being tested without the need of any special
heating
system.
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