Hello, everyone,

I met another problem on SU-8 process.

Wrinkles are found on the sidewall surface of SU-8 structure, like 5 X 1 X
0.4 mm cuboid and 50 X 0.1 X 0.4 mm narrow cuboid, after exposure and
development.
The soft-bake temperature is 100 celsius degree/ 2hours, and the post
exposure bake temperature is 100 celsius degree/ 1hour. The exposure doses
are from 600-1200 mJ/cm2.
Also delamination was found after development. I thought this is due to
internal stress, and I tried to lower the post-exposure-bake temp. down to
80 celsius degree/ 2 hour.
But wrinkles are still there, and the amount is not reduced obviously.
Is anyone have some idea about this problem? Please give me some advice.

Thanks a lot !

wrinkles are shown in this picture:
http://farm3.static.flickr.com/2147/2547007289_bbd840d815.jpg?v=0


--
Best Regards,

郑瑞麟

Ruilin Zheng

Address:
Pen-Tung Sah MEMS Research Center,
Xiamen University, Xiamen,361005,
P.R.China