It depends. ARCs are most useful on highly reflective layers or when you are
pushing the resolution of the exposure tool.
   Grating structures are very sensitive to focus and exposure.

Regards,
  Robert

-----Original Message-----
From: csh@u.washington.edu
Subject: [mems-talk] antireflection coating?

I am working on the two beam interference grating structure with 0.5~1um
thick photoresist. So far I did not use antireflection coating but I cannot
still get grating.
I am just wondering if anyone have any experience about how much differences
between with antireflection coating and without it?