| 摘要 |
PROBLEM TO BE SOLVED: To effectively prevent a drop in the insulating reliability between conductor circuits by a method wherein the amount of a catalyst nucleus, for electroless plating, which is left in a conductor-circuit nonformation part out of the surface of a resin insulating layer is set at a specific value or lower in terms of metal ions. SOLUTION: A board is coated with a photosensitive adhesive solution by using a roll coater, and an adhesive layer 2 for electroless plating is formed. The surface of the adhesive layer 2 is roughened, a palladium catalyst is given to the roughened board, and the amount of a catalyst nucleus, for electroless plating, at 2μg/cm<2> or lower in terms of metal ions is given to the adhesive layer 2 for electroless plating and to the surface of an opening for a via a hole. After that, an electroless copper-plated film 12 is formed on the entire roughened surface of the adhesive layer 2 for electroless plating, a plating resist 3 is formed on it, and an electrolytic copper-plated film 13 is formed in the nonformation part of the plating resist 3. A conductor circuit 4 is formed of the electrolytic copper-plated film 13 and of the electroless copper-plated film 12. |
