|
Hi All,
I'm the phototech here at the McGill University Nanotools facility and have what I would guess to be a newbie question.
We are spin coating MicroChem's SU-8 25 resist onto six inch wafers and achieving a (basically) uniform coat of 40um. A pre-expose bake is completed at 65C/5min then at 95C/15min. Wafers are then exposed in three intervals of 10secs with a gap of 60secs inbetween, this gives a dose of ~300mj.
A post expose bakee is then done at 65C/4min then at 95C/20min.
We develop in a bath of MicroChem's developer, while the geometries seem to develop well, they also lift off from the wafer, we have tried rinsing in Alcohol as well as developer with the same results...the features wash off the wafer.
Is this a common problem with a ready solution? Is there an HMDS-type product for SU-8?
Any insite would be greatly appreciated.
Best Regards,
Neal Lemaire
|