Hello Jeffrey,

It may be that the resist is hardened during the metalization process. You can
descum the wafer for about 5 mins first and then dip it in the stripper. Descum
after that to remove any unseen residue. We use ST33 or ST22 at 80C and it works
very well for us. Also you might want to look into the temperature of your
metalization process and try to lower it.

Deepa

Nodes Norbert  wrote: Hello Jeffrey.

Maybe the substrate temperature was too high during metallization
process.
It should not exceed the usual soft bake temperature for AZ9260, or else
at least some resist is not soluble anymore in Acetone or other
solvents.

If the temperature (hard bake) cannot be avoided, ashing might be the
only alternative.