Maybe the film stress may explain the collapse. You may want to change
the deposition conditions or anneal the metal film to change its stress.

Regards,
Pierre x286
-----Original Message-----
From: Ramesh Narayanan
Subject: [mems-talk] cantilever bending problem ?

I have fabricated array of mico cantilevers using aluminum. dimension
are length=300um, width=200um, height=2um.(air gap3-4um) i am using
sacrificial material and washing it away to free the cantilever. But most
of the cantilevers have collapsed. I have also calculated the bending due
to its own weight and i am getting answer in nanometers. Is this happening
because of the E(Al)=70GPa or dimension is too large and collapsing due
to its ownweight? Or am i making calculation mistake?