the wrinkling may be due to the glass transition temperature being too low. I
have observed this problem with aluminium
on other polymer films. I understand that a higher baking temperature before
metal deposition can increase the glass
transition temperature in some polymers and hence prevent the surface flowing,
causing wrinkles in a subsequent heat
process.

I noted that the wrinkling did not occur when there was no metal, irrespective
of the heat processes. Can anyone explain
this?

Good luck

Anthony Holland



Dr. Anthony Holland
Research Fellow
Australian Photonics Cooperative Research Centre
School of Electrical and Computer Systems Engineering
RMIT University
GPO Box 2476V
Melbourne
VIC 3000
AUSTRALIA

Tel. 61 3 9925 2150
Fax. 61 3 9925 2007
>>> leidongmao@yahoo.com 04/10/04 3:50 AM >>>
Hello all,

    We met a SU-8 wrinkle problem and would like to
hear any suggestion. The process is to pattern gold on
the un-exposed SU-8 resist. We first piranha etched
the glass slides and baked it for 1hr@200C. The
spun-on SU-8 resist looked good after soft bake. Then
gold was sputtered onto the resist, and it was
patterned by using Shipley 1813 positive resist. After
that, the gold was etched in Transene gold etchant TFA
(a complex of KI/I2), rinsed in DI water, baked at 90C
for 30 mins. The wrinkles showed up during the baking.
Does anyone have the same experience? Any suggestion
welcomed.


__________________________________
Do you Yahoo!?
Yahoo! Small Business $15K Web Design Giveaway
http://promotions.yahoo.com/design_giveaway/

_______________________________________________
MEMS-talk@memsnet.org mailing list: to unsubscribe or change your list
options, visit http://mail.mems-exchange.org/mailman/listinfo/mems-talk
Hosted by the MEMS Exchange, providers of MEMS processing services.
Visit us at http://www.memsnet.org/