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Manual matching:
The handling of the manual matching takes a certain extent of patience and sensitivness.
The display
‘Forward’
shows the forward power of the generator (that means the power which is
sent into the chamber). The display
‘Reflected’
shows the reflected power of the generator (that
means the power which is sent back to the generator). The forward power should meet the value
which is expected for the process power. The
reflected power is ideally at 0%
, but at the
utmost 20%, because reflected power may loads or damages the generator.
The matching will be operated with the two
rotary knobs
C1
and
C2
, which shift the tuning
capacitors.
These two knobs have to be turned slowly, because the
matching reacts very sensitive
. Keep
an eye on the displays during the adjustment.
Beginning with C1 the knobs shall be set in that way, that the forward power is on the maximum
and the reflected power on the minimum.
The
rolling direction is arbitrary
. The capacitor changes within one turn over his complete
range.
The matching has to be
adjusted at each process start
and sporadically controlled and
matched during the process.
Handmatching figure:
R
iG
= Internal Resistance Generator
R
iP
= Internal Resistance Plasma chamber
C = Capacitor
Chamber
Summary of Contents for femto
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