>> >> 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 > > I use gold on titanium routinely on both glass and silicon substrates with excellent results. Perhaps you are seeing a difference in method of deposition. The metals must be vacumn deposited in-situ, or you may form an oxide on the Titanium, which would degrade adhesion of the gold.