A method for manufacturing traces of a printed circuit board (PCB) comprises an application of the periodic pulse reverse (PPR) pattern plating process. In the first stage, walls and bottoms in drilled holes of the PCB are modified with reduced graphene oxide (rGO) so that the vias can be formed by filling with copper and a very thin copper layer can be formed on the substrate through the electroplating process. In the second stage, a pattern of very fine traces with width/space less than 30/30 μm is formed on the thin copper layer and then the traces are formed through the PPR pattern plating process. After removing unwanted copper layer, the traces with even thicknesses and square profiles are achieved and thus conform to requirements of the high density interconnection (HDI) technology.
展开▼
