MANUFACTURING METHOD OF MULTILAYER PRINTED WIRING BOARD AND MULTILAYER PRINTED WIRING BOARD

摘要

A wiring substrate is manufactured by attaching an adhesive protective film to a metal-foiled laminate sheet, forming bottomed via holes by partially removing the film and an insulating film, filling conductive pastes into the holes, and peeling the film. A wiring substrate is manufactured by forming an adhesive protective layer so as to cover a patterned metal foil on a metal-foiled laminate sheet, forming bottomed step via holes by partially removing the layer and an insulating film, filling conductive pastes into the holes, and peeling off a protective film. The wiring substrate and the second wiring substrate are laminated in such a way that protruding parts of the pastes come into contact with respective protruding parts of the pastes.

主权项

1. A manufacturing method of a multilayer printed wiring board comprising:
attaching an adhesive protective film having a weak adhesive layer formed on one side thereof to a single-sided metal-foiled laminate sheet having a first insulating resin film and a first metal foil on a front face of the first insulating resin film in such a way that the weak adhesive layer contacts with a rear face of the first insulating resin film; forming a bottomed via hole that has a bottom face with the first metal foil exposed therefrom by partially removing the adhesive protective film and the first insulating resin film; first printing of filling a conductive paste into the bottomed via hole by a printing method; peeling off the adhesive protective film from the first insulating resin film and causing a part of the conductive paste filled in the bottomed via hole to protrude from the first insulating resin film, and thereby obtaining a first wiring substrate; forming, on a double-sided metal-foiled laminate sheet having a second insulating resin film and second and third metal foils respectively provided on a front face and a rear face of the second insulating resin film, a piercing mask by patterning the second metal foil; forming an adhesive protective layer including an adhesive-agent layer that covers the front face of the second insulating resin film and buries the patterned second metal foil and a protective film that is laminated on the adhesive-agent layer; forming a bottomed step via hole that has a middle part with the piercing mask exposed therefrom and a bottom face with the third metal foil exposed therefrom by partially removing the adhesive protective layer and the second insulating resin film; second printing of filling a conductive paste into the bottomed step via hole by a printing method; peeling off the protective film from the adhesive-agent layer and causing a part of the conductive paste filled in the bottomed step via hole to protrude from the adhesive-agent layer, thereby obtaining a second wiring substrate; and laminating in which the first wiring substrate and the second wiring substrate are laminated in such a way that a protruding part of the conductive paste filled in the bottomed via hole of the first wiring substrate comes into contact with a protruding part of the conductive paste filled in the bottomed step via hole of the second wiring substrate, and the laminated first and second wiring substrates are heated to be integrated with each other.