You cannot deposit gold directly over copper. You need first to deposit a Ni (nickel) barrier.
That is why the process is complex and expensive.
The industry has two slightly different ways to do it, INIG and ENIG which differs only on the way the nickel is deposited. Some other use a process called ENEPIG which is even more complex as ir uses a palladium intermediate between the nickel and the Gold.
In all those processes, E stand for Electroplating while I stands for Immersion(chemical).
Just my $0.02,
Jean-Paul
N1JPL
> On Sep 20, 2016, at 1:09 PM, anickol@... [Homebrew_PCBs] <Homebrew_PCBs@yahoogroups.com> wrote:
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> Sorry to inform you, but there is no simple ans inexpensive way to put gold on copper. I've got some recipes, which contain materials like gold cyanide, potassium cyanide, etc. When I first saw these, I thought that I'd better abstain from this.
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