Try to use Ti as adhesion layer.

Shay

-----Original Message-----
From: [email protected] [mailto:[email protected]]
On Behalf Of Heiko Pr??ner
Sent: Wednesday, April 09, 2008 1:23 PM
To: General MEMS discussion
Subject: Re: [mems-talk] Hf resistant Adhesion layer for Au on Si

Dear All,

thank you for your replies on my question about the adhesion problem of my
thermally treated Cr/Au layer (see below).

Your suggestion about the interdiffusion of Cr and Au seem to be correct. I
found out that the thermal step already destroys the adhesion of the films.
Also I tested some chips with 20nm Cr/ 200nm Ni / 200nm Au which I already
had here. They worked fine even for 3 hours at 380degC. So Ni as diffusion
barrier seem to work. Due to stress reasons 200nm Ni might be to thick for
my application. Does anyone know what minimum thickness for Ni as diffusion
barrier is necessary?