If you had some high-temperature processing, there might be TiO2 on the Au/ambient interface. Someone said Ti may diffuse through the grain boundary of Au. I am not sure if this is what happened to your samples. On Fri, Mar 13, 2009 at 12:50 AM, Yoshi Sakatawrote: > Hi All, > > I'm trying to clean the Pyrex wafers with NH4OH + H2O2. The wafer has > the Au/Ti film on the surface. I have the oxide or something on the > surface of Au. So it is very difficult for me to have the electrical > contact with the surface of Au. Does anybody know what is on the > surface of Au, how I can remove this oxide? > > Regards, > Yoshi