Specifications

Appendix B
SRS Residual Gas Analyzer
3
background peaks, the operating pressure should be kept as high as possible. The
background can be minimized by designing the tubing such that the effective pumping
speed at the RGA ionizer is as high as possible. Figure 2 shows two layouts that both
have the same “signal” level. The layout with the RGA at the end of a small tube has a
small effective pumping speed and will show a larger background level.
Turbo
Pump
Signal
RGA
Ionizer
Signal
RGA
Ionizer
Background
GOOD
BAD
Background
Turbo
Pump