All,

One correction - AZ EBR 70/30 does not contain EGMEA - It contains PGME
(70%) and PGMEA (30%) - AZ ceased using EGMEA when it was discovered to
have negative affects on reproductivity

Best Regards,
Chad Brubaker

EV Group       invent * innovate * implement
Senior Process Engineer - Technology - Tel:  480.727.9635, Fax:
480.727.9700  e-mail: c.brubaker@EVGroup.com, www.EVGroup.com

-----Original Message-----
From: mems-talk-bounces@memsnet.org
[mailto:mems-talk-bounces@memsnet.org] On Behalf Of Edward Sebesta
Sent: Tuesday, March 11, 2008 6:19 AM
To: General MEMS discussion
Subject: RE: [mems-talk] Edge Bead Removal

I just implemented an EBR process that gives a wafer edge resist removal
and is perfection.

The EBR ridge is a known issue with EBR processes, but it has its fixes.

I am assuming that you are doing EBR with a novolak resin based positive
resist.

1. Use an EGMEA type solvent instead of acetone. One product is AZ70/30.
Basically you don't use acetone, but you use the solvent system of the
resist itself to do the EBR. It doesn't have to be the exact solvent
system of your resist, but a solvent that is similar to those used to
make novolak resin resists.