HI MEMS people,

Sorry for late response as I was busy.

Just recently, I did lift off of Au on Cr on Si substrate to act as an
electrode. Again, applying electricity peels off the Au layer. My
classmate did similar work and did some experiments and found out that
the reason for peeling problem is that the electrochemical (EC) reaction
of Cr and therefore the Au fly out.

Perhaps:
1. Use a lower voltage such that redox reaction with Cr is stopped.
2. If for electrode purpose, coating a dielectric layer (maybe parylene)
may obstacle the EC attack of Cr.

Zeta Tak For YU
UCLA



Hongjun-ECE wrote:

>If you were done with the following two points, the film's adhesion should
>
> be good,
>
> 1. Plasma descum before any deposition
> 2. Deposit Cr or Ti and then Ag in the same run of the deposition.
>
> If the adhesion is good, the Ag film peering off might be caused by the
> electrochemical reaction, which the adhesion layer was sacrificed as
> anode.