CMP Challenges

[Ed Myers]

All,

Over the years I would get occasional reports of polishing rate 
asperities.  This may happen more than I'm aware, since often times 
problems or concerns go unreported.  During these isolated 
excursions, I was never able to find any correlate to these problems.

Recently I have changed out a number of our membranes within a sort 
time period.  This has resulted in many more reports of polishing 
problems.  I feel pretty confident there is a correlation to our 
membrane assemblies and our polishing rate excursions.  I am working 
with the US parts supplier and GnP to understand why we are so 
sensitive to the changing of the membranes.  We are trying to 
determine if we received incorrect assemblies, if there is a way to 
condition the assemblies or if we need to modernize our wafer heads.

I will keep you appraised to any findings or developments as they become clear.

Regards,
Ed