Michael,

Based on your current metallization stack and temp requirement, your
best option would be Au-Sn eutectic wafer bonding. There are other
options available (Cu-Sn eutectic, Au-Au etc) but that would require
changes to your stack and/or CMP depending on the surface roughness of
your wafers.


Regards
Sumant Sood

-----Original Message-----
From: [email protected]
[mailto:[email protected]] On Behalf Of
[email protected]
Sent: Sunday, March 13, 2011 10:54 AM
To: [email protected]
Subject: [mems-talk] Simultaneous wafer level electrical and hermetic
bond

Hi fellow fabricators,

   I am looking for suggestions to make a wafer level bond that will
yield both low resistance electrical contacts between 2 wafers and
simultaneously produce a hermetically sealed cavity at a known reference
pressure.  The peak temperature should be <300 deg C and my metalization
is currently Au/TiW.  The ideal solution would no require chemical
mechanical polishing.  We have a nice Suss wafer level bonder.  We have
explored using BCB for the seal but I not sure what the best approach
would be for electrical connections.

Thanks in advance,

  Michael