Hi,

I have tried to figure out the main factors that cause scumming for small
trenches (i.e 10um) in my negative thick resist (up to 45um).  They are *resist
(temperature,RH), exposure, developer (temperature, RH, time), Soft Bake
(time/temp), PEB (time/temp).*  I'm going to run DOE but need help from your
expertise, so it may save my time and energy.  In the same token, which of
those are main factors for 10um ring lifting, perhaps *surface
cleanliness* should be included.

Thanks in advance,
Paul