Abstract: A method includes the steps of forming a first metal foil (82) on a surface of an insulator substrate (1a), drilling, with a thermosetting resin film (84) temporarily fixed to an opposite surface of the substrate, a through hole (86) simultaneously in the first foil, the substrate, and the resin film, simultaneously heating and vacuum-pressing the first foil, the substrate, the resin film, and a second metal foil (87) brought into contact with the resin film to obtain an intermediate board in which a bottom of the through hole is covered with the second foil and has a corner with a corner rounded portion (93) formed by the resin film, and forming a metal plating layer (95) on the first and the second foils, on the bottom and an inner wall of the through hole, and on the corner rounded portion to obtain a final printed wiring board.

Abstract: On carrying out a hole filling method for a printed wiring board having an interlayer connection hole, first and second printed wiring boards (1 and 2) are prepared, each of which has the interlayer connection hole. The first printed wiring board is placed on a bottom plate (7). On the first printed wiring board, a first hole guide plate (8) having a first guide hole formed at a position corresponding to the interlayer connection hole of the first printed wiring board is placed in such a manner that the first guide hole is coincident with the interlayer connection hole of the first printed wiring board. A hole filling resin (9) is superposed on the first hole guide plate. On the hole filling resin, a second hole guide plate (10) having a second guide hole formed at a position corresponding to the interlayer connection hole of the second printed wiring board is placed.

Abstract: A method includes the steps of forming a first metal foil (82) on a surface of an insulator substrate (1a), drilling, with a thermosetting resin film (84) temporarily fixed to an opposite surface of the substrate, a through hole (86) simultaneously in the first foil, the substrate, and the resin film, simultaneously heating and vacuum-pressing the first foil, the substrate, the resin film, and a second metal foil (87) brought into contact with the resin film to obtain an intermediate board in which a bottom of the through hole is covered with the second foil and has a corner with a corner rounded portion (93) formed by the resin film, and forming a metal plating layer (95) on the first and the second foils, on the bottom and an inner wall of the through hole, and on the corner rounded portion to obtain a final printed wiring board.

Abstract: On carrying out a hole filling method for a printed wiring board having an interlayer connection hole, first and second printed wiring boards (1 and 2) are prepared, each of which has the interlayer connection hole. The first printed wiring board is placed on a bottom plate (7). On the first printed wiring board, a first hole guide plate (8) having a first guide hole formed at a position corresponding to the interlayer connection hole of the first printed wiring board is placed in such a manner that the first guide hole is coincident with the interlayer connection hole of the first printed wiring board. A hole filling resin (9) is superposed on the first hole guide plate. On the hole filling resin, a second hole guide plate (10) having a second guide hole formed at a position corresponding to the interlayer connection hole of the second printed wiring board is placed.