Dear colleges,

I will use 20um and 50um thick device layer SOI wafer to fabricate a large
structure(2000um by 2000um square) with DRIE. To release the structure
with HF, I need to design etching holes.

I wonder what's the appropriate etching hole size and hole offset  should
I adopt to smooth the HF etching process but still keep the size(mass) of the
big structure as much as possible?

Thanks for your possible help!

Jing

MEMS Lab.,
Dept. of Mechanical Engineering,
Univ. of Maryland, College Park,
MD, 20770