| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of forming a via hole in a multilayer wiring board and a multilayer wiring board with high reliability at a low cost by forming a via hole used as a conductor by pressworking. SOLUTION: In this method of forming a via hole in a multilayer wiring board, a conductor 15 for connecting conductive metal foils 11A, 11B on both sides of an insulating member 12 is constituted at a predetermined position of a multilayer wiring board 10 where a plurality of conductive metal foils 11A, 11B are laminated via an insulating member 12. The conductive metal foil 11A on one side of the multilayer wiring board 10 is placed on the side of a backup plate 13. A draw punch 14 is pressed on the conductive metal foil 11B on the other side to form a concave part 16 in a part of the conductive metal foil 11B so that the insulating member 12 is penetrated. The concave part 16 is brought into contact with the conductive metal foil 11A on the other side to constitute the conductor 15. |
