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?

Kind regards,
Heiko

=?iso-8859-1?Q?Heiko_Pr=FC=DFner?=  writes:
> Dear all,
>
> I had a 20nmCr/ 200nmAu film sputtert on silicon. This setup has been
> treated at 350degC for an hour. At the final Hf etching step which I used
> to remove the BOX of an SOI wafer the Au film peeled of.
>
> Does anybody have an explanation? Do I need a diffusion barrier between
> the Cr and the Au? Or has anyone a suggestion for another adhesion layer?