Method of preparing a substrate surface for conformal plating

摘要

Bridging between electrically conductive circuit features during conformal plating is prevented by avoiding the deposition of catalytic seed material onto non-circuit areas of the substrate. Preparatory to forming electrical circuit features on a nonconductive substrate by the full additive process, extraneous seed material is either trapped between two layers of a photoimageable film, whereby it is unavailable during plating, or deposited on the surface of an aqueous photoimageable film, which is removed prior to plating. The method embodying the present invention eliminates the need for seed removal after initial plating and prior to conformal plating of a precious metal over the initial plating.