>
> Gold will stick well to silicon if there is no oxide present.  An HF dip
> immediately preceeding the metallization is usually sufficient, although a
> pre-dep sputter etch is a good idea if you can sputter the metal (depends
> on device surface state constraints).  To get good adhesion on nitride, I
> would recommend a thin chrome or titanium adhesion layer.  Titanium is nice
> because it's biologically inert and etches easily in very dilute HF
>
>
>
>
I don't believe titanium to be an appropriate choice of adhesion
layer for gold deposition. We have tried and it didn't work for
us. Even a simple gold wire doesn't stick to a surface with
titanium on it. I am not sure if there are any especial
circumstances where gold sticks well to titanium.

--
Bahram Ghodsian

School of Engineering Science               voice: 604-294 1985
Simon Fraser University                       fax: 604-291 4951
Burnaby, BC, V5A 1S6, Canada                 ghodsian@cs.sfu.ca