Dear MEMS colleague,

I'm working on fabricating microchannel with SU-8. There are several
thermal cycles which made the SU-8 layer very hardened. Although the SU-8
layer is unexposed, it's difficult to develop the SU-8 away. I'm wondering
if this caused by so many thermal cycles.

Another possibility is that I wash the unexposed SU-8 with acetone for a
while and it seemed that the SU-8 can be dissolve in acetone a little bit.
After I rinse it, I put it back into the developer for development. I'm
wondering if the difficulty for development is caused by the acetone wash.

Did anybody meet this kind of problem before? And are there any strong
solvent which can selectively (corresponding to exposed SU-8) get rid of
unexposed SU-8?  Please let me know if you have any idea of this problem. I
really appreciate your help.

thank you


Li Wang
Graduate student
Mechanical Engineering Department
Carnegie Mellon University
Pittsburgh, PA 15213
Tel: 412-268-2514
Fax: 412-268-3348
Email: [email protected]