From eenriquez at snf.stanford.edu  Fri Mar 20 15:47:16 2009
From: eenriquez at snf.stanford.edu (Elmer Enriquez)
Date: Fri, 20 Mar 2009 15:47:16 -0700
Subject: STSetch status
Message-ID: <49C41CF4.5080005@snf.stanford.edu>

     The backside He flow is still inconsistent and the C4F8 flow is 
questionable.  The plan is to install a metering valve to better 
regulate the He flow.  Currently, the flow is regulated using a nupro 
valve with a stopping screw.  As far as running the etcher with a 
fluctuating He flow, the important parameter to watch is the backside 
pressure (9 Torr).  As long as the pressure is stable, the actual flow 
has little effect on the wafer cooling.  
     We are also planning to replace the C4F8 flow controller with a 
newly calibrated MFC.  Currently, we cannot trust the flow readings 
indicated by the flow meter because the pressure vs flow test that we 
ran when compared to previous tests shows that the flow has roughly 
doubled.  I think that the higher C4F8 flow will result in more grassing ??
     All the repair work should be completed by 3 pm on Monday 3/23.

Elmer


From gyama at snf.stanford.edu  Thu Mar 26 13:04:38 2009
From: gyama at snf.stanford.edu (Gary Yama (SNF))
Date: Thu, 26 Mar 2009 13:04:38 -0700
Subject: reservation removed today 2-4pm, FRI noon-2pm, wafer finished early
Message-ID: <49CBDFD6.5090301@snf.stanford.edu>