| 摘要 |
PROBLEM TO BE SOLVED: To provide an efficient manufacturing method of a high-density multilayer wiring board which can facilitate formation of a fine conductor pattern. SOLUTION: A laser beam is projected onto the organic film surface of an adhesive-applied metal foil 5 which has an insulating adhesive layer 3 provided on one side of a metal foil 2 and a separable organic film 4 provided on the surface of the insulating adhesive layer, thereby forming a hole reaching to the metal foil at a position where electric connection between layers is to be made, fills the hole with a conductive paste 7, and the conductive paste is semi-cured. Then, the organic film 4 is separated, and the adhesive-applied metal film 5 is placed over the surface of an inner layer circuit board 1 in such a way that the hole in the adhesive-applied metal foil, which is filled with the conductive paste, is aligned with the connection portion of an inner layer circuit of the inner layer circuit board, and they are pressed and heated into a laminate. Then, the outer metal foil is made thinner in the widthwise direction and the unnecessary portion of the metal foil is etched out, thus forming a conductive pattern. |
