| 摘要 |
PROBLEM TO BE SOLVED: To provide a manufacturing method for multilayer printed wiring board with which a portion just above a via hole can be flattened and a surface mount area can be secured wide. SOLUTION: A recessed part 8 for the via hole is formed on a resin part 7 of a resin sheet 6 with copper foil by direct laser working, the resin sheet 6 with copper foil filling the inside of the recessed part 8 by electrolytic plating is previously produced, such a resin sheet 6 with copper foil is heated and pressed on both the sides of an inner layer board 1, and a conductor circuit 13 of an outer layer is formed by etching so that a multilayer printed wiring board 14 can be produced. By applying electrolytic plating while utilizing copper foil 10 of the resin sheet 6 with copper foil as a power feeding layer, electrolytic plating 9 is grown only in the recessed part 8 of the via hole, and the recessed part 8 can be completely filled by electrolytic plating 9. |
