New Policy on Segregation of Etch Chemistries, effective immediately

[Mary Tang]

Greetings pquest users:

As you probably are aware, there has been a lot of discussion about the 
policy of segregating Cl2 from fluorine etching.  Following a meeting 
with the Etch Quality Circle, where researchers from the Vuckovic, 
Harris, and Wong labs were in attendance, along with Jim Kruger, our 
pquest superuser, the new policy was defined.  A survey of pquest users 
did not indicate undue burden with the proposed change.  The new policy 
is as follows:

- Pquest will undergo a wet/dry clean sequence on the 1st and 3rd 
Mondays of every month.
- Etches during the following 7 days (inclusive of the 2nd and 4th 
Mondays) will be restricted to recipes that do not contain Fluorine, at 
chuck temperatures <=50C.

This policy will increase the number of Fluorine-recipe days a month and 
no longer limit them to the end of the month.

This new policy is effective immediately.  The monthly chamber clean is 
scheduled for the morning of Monday, Nov. 3.  The semimonthly schedule 
starts then.

Many thanks to everyone for your feedback and willingness to work this 
out!  There are several very happy students now..



The Etch Quality Circle