21
PIPS II Owners Manual and Users Guide
Figure 1-3 Work chamber, cross-section view.
1.3.
Vacuum System
PIPS II has a compact, oil-free vacuum system consisting of a molecular drag
pump (MDP) backed by a 2-stage diaphragm pump (DP). The vacuum system
is designed to hold vacuum when the power is turned off. The working
vacuum can be reached very quickly when the power is resumed.
1.3.1.
The Pumping system
The MDP has an argon pumping speed of 80 L/sec. It is in series with a 2-
stage diaphragm pump (DP) that maintains a backing pressure for the MDP of
less than 10 Torr and a chamber base pressure in the 10
-6
Torr range. The
pumping time from atmosphere to near the base pressure is typically less than
15 min. The console is cooled by a single fan mounted on the rear panel that
directs air onto the MDP.
1.3.2.
The Pumping Manifold
The Pumping Manifold contains the cold-cathode gauge tube and the MDP,
which is offset from the Work Chamber to minimize any possibility of debris
