Parrish,

I have found this flow to give a great neg profile:


Coat    5214 Resist
Softbake        Bake 5 min @100C contact
Cool    Quickly cool
Expose
PEB bake        118c 1:30 min
Cool    3 min slow cool
Expose  60 sec
Develop 45 sec at RT, 2 min rinse

Ad
StarCryo Electronics

-----Original Message-----
From: mems-talk-bounces+ahall=starcryo.com@memsnet.org
[mailto:mems-talk-bounces+ahall=starcryo.com@memsnet.org] On Behalf Of
Parrish Ralston
Sent: Tuesday, February 22, 2011 7:59 AM
To: mems-talk@memsnet.org
Subject: [mems-talk] Overcut AZ5214 profile

I was wondering if anyone has a recipe for AZ5214 as a negative photoresist
(or any other negative photoresist) that has good step coverage, and overcut
sidewalls.

I have been trying for a while to use positive photoresist as a continuity
layer that resides between a MMIC chip set in a cavity and a Ti/Au seedlayer
for electroplating.  I deposit KMPR on top of the seed layer as an
electroplating mold and the solvents in the KMPR react with the positive
photoresist.  It doesn't seem to matter than I have thickened my seed layer
in attempts to better isolate the two layers.

So I would like to try and use a negative resist which hopefully will hold
up better to the KMPR.  But I still need good step coverage and a good,
overcut sidewalls so my seed layer is still continuous.

Thank you,
Parrish