Stanford Research Systems RGA100, Operating Manual And Programming Reference

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8-16 CDEM Pre-conditioning
SRS Residual Gas Analyzer
CDEM Pre-conditioning
The following preconditioning procedure is recommended for the first pump-down and
initial operation of a new CDEM:
1. Pump overnight prior to initial application of voltage.
2. Begin operation at the lowest voltage possible, working up to the voltage required to
produce observable peaks.
3. Limit the initial operation to trace peaks with gradual increase in abundance levels
over the first two hours of operation of a new CDEM.
All CDEM’’s undergo an initial cleanup phase during which absorbed gases are removed
from the active surface. If during this time the detector is exposed to high input currents
permanent gain degradation by as much as a factor of ten may result. The steps described
above help to control initial outgassing and are performed in order to precondition the
CDEM. Optimum sensitivity and longer lifetime will result if the recommendations are
followed.