Patent ID: 7378227
Filing Date: 2008-05-27
Classification: C25D,H05K

Abstract:
1. The method of making a printed wiring board without the formation of slivers, comprising the steps of: a. providing a substrate having a plurality of thin circuit lines thereon; b. applying a solder mask over the circuit lines onto which a commoning layer is not to be applied; c. applying a seed catalyst layer over the solder mask and over all surfaces of the substrate that are not covered by the solder mask; d. applying a thin metal commoning layer of electroless copper on the substrate and on the circuit lines to a thickness sufficient to achieve electrical continuity; e. applying a photoresist over the thin commoning layer; f. removing the photoresist to expose only the portion of the commoning layer covering the circuit lines as well as the side walls of the circuit lines; and g. electrodepositing a conforming layer of a metal more noble than copper over the exposed commoning layer, covering the top and extending down the sides of each circuit line, at least to the point at which the conforming layer of electroless copper is intersected by the more noble metal.