I've been having trouble e-beam evaporating Pt on photoresist for
lift-off, at 0.5A/s. The resist seemed to be cracking and/or reflowing
after a few minutes, but it was ok since we only needed about 200A of
Pt. The substrate temperature also rises pretty quickly, to about
150C. Assuming the resist damage was due to excessive heat damage, I
installed a water-cooled substrate holder. Strangely, the resist
damage is significantly worse now. It takes just 10 seconds before the
resist becomes completely deformed, which can be visually seen through
the viewport. Except for the substrate temperature, which is at 30C,
everything else is identical during evaporation. Anyone has clues on
what this could be due to?