MANUFACTURE OF BUILDUP PRINTED WIRING BOARD

PROBLEM TO BE SOLVED: To provide a method for manufacturing a buildup printed wiring board in which electrical characteristics of a fine wiring are improved at low cost. SOLUTION: In this manufacturing method, a pattern of three-layer structure of copper etching resist plating copper is plated on a core board 1, and then a recessed part formed by etching an upper copper plating layer other than a via pattern part 5 on a pattern plating is filled with photosensitive insulating resin 2 for insulating process. There is no necessity for forming a via hole by laser process, etc., in a conventional manner, and the whole circuit is buried in the insulating material which is favorable for security of electrical characteristics. Further, the photosensitive resin is used as insulating material, so that it is possible to remove the insulating material sticking on the circuit in an exposing/developing process without performing mechanical polishing.