Hi to all,

 

We've just completed a batch of Polyimide multilayer PCB's and Ni/Au'd
as our solderable finish. 

We have noticed that the Ni/Au has plated onto and around the pads, and
joined up some quad pack pads.

I seem to recall something about Zinc Octanoate acid leaching out from
the surface of the Polyimide, which acts as a catalyst for the solution
to get a grip and plate onto what is bare substrate, or have I got the
wrong end of a long stick?

Would a UV bump lock the substrate surface prior to the finish, or are
there other remedies? (we already IR bake resist at upto 150oC prior to
the application of Ni/Au)

 

Colin McVean

Production Manager

Artetch Circuits Limited

Tel: 01903 725365

 


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