Comment stsetch SNF 2007-12-21 10:56:53: Wet cleaned chamber.

[eenriquez at snf.stanford.edu]

Cleaned the chamber.  Removed heavy polymer build on chamber walls and platten.   Replaced the backside He lip seal.
Before the PM, I found the backside He pressure was set at 4 Torr.  Even at that level, I was unable to run a recipe because of high backside He leak rate.  After the PM, I was able to run the O2 clean recipe at a backside He pressure setting of 8.5 Torr.  Press setting is currently at ~7 Torr.
Ran O2 clean for 2 hours with no problems.  Chamber leak rate is 5 mT/min.