You will have to electroplate (or electroless) nickel on the copper before the gold. Shay -----Original Message----- From: mems-talk-bounces@memsnet.org [mailto:mems-talk-bounces@memsnet.org] On Behalf Of BastiWicklein@aol.com Sent: Monday, June 09, 2008 8:04 PM To: mems-talk@memsnet.org Subject: [mems-talk] Au electroplating on Cu seed layer Colleagues, I'd like to perform Au electroplating. For particular PVD reasons I cannot provide an Au-seed layer. Since Cu forms an alloy with Au I was wondering weather it is feasible to electroplate Au onto Cu. Since I'm cautious with Gold I was wondering if you could provide me with some input in this matter before I start electroplating. So far I'm planing to use a sulfite based Au-electrolyte since CN-based electrolytes might not be good with photoresists. The question mark here is how the Cu behaves in such a solution and if it might dissolve in the Sulfite electrolyte etc....or if another solution might be better.... I would appreciate any comments in that matter!