Dear MEMS-community,

I wonder if anybody of you could give me some information about the
behavior of SU-8
concerning the shrinking (or swelling) subsequent to illumination and PEB.
Guerin 1997 reports a shrinkage of 7.5%.
I have been working with SU-8 for years and my experience is quite
different:
If I measure the surface topography after exposure and PEB I found that
the areas
exposed to UV light are approx. 1% higher than
the surrounding (non-exposed) areas.
This happens regardless of softbake, post exposure bake time and temperature
and overall layer thickness.
What is your experience ?
Many thanks
Peter

--
Vienna University of Technology
Institute of Sensor and Actuator Systems
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Austria

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