Hello,

I'm having an odd problem and would greatly appreciate any advice.  I am
developing a mems device consisting of patterned aluminum on silicon wafers.
Some of the patterned aluminum is on the silicon substrate and some is on a
silicon dioxide layer.  After dicing,  packaging and wirebonding the die, I
perform a 20 second clean in a Technics PE2A Plasma Etcher at 300W with 90%
SF6 with 10% O2.  I do this to clean the exposed silicon surface before
release etching with XeF2 in a separate etcher.  During the cleaning, some
of the packaged die experience a phenomena where the aluminum traces explode
like a fuse.  I think this may be due to charge build-up during the 20
second clean?  How do I prevent this from happening?  We've tried thermal
grease on the back of the packages without improvement.  This phenomena only
happens about half of the time.

Sincerely,

Robert Dean

RF CMOS Designer / Project Manager

MEMS Optical, Inc.
205 Import Circle
Huntsville, AL 35806

(256) 859-1886     Voice
(256) 859-5890     Fax