The missing adhesion layer is your most likely culprit.

-----Original Message-----
From: [email protected] [mailto:mems-talk-
[email protected]] On Behalf Of Shane GUO
Sent: Monday, December 05, 2011 8:52 AM
To: [email protected]
Subject: [mems-talk] e-beam evaporation of gold

Hi all,

I am doing some work to evaporate Au to a substrate with some SU-8 bumps. To
cover one of the side walls the sample stage was tilted. I found the electric
connection after Au etching was not consistent. Sometime the electric connection
was good sometimes failed. I am wondering what are the potential causes? Our Au
thickness was 100nm and there was no adhesion layer, Cr or Ti, under gold. Are
these two the culprits - too think gold layer or no adhesion layer? Or there
should be something else I should have taken care of but neglected?

Thank you in advance