MANUFACTURE OF MULTILAYERED CIRCUIT BOARD

摘要

PURPOSE:To provide a method of manufacturing a multilayered circuit board wherein an interlayer connection part can easily be formed when the distance between circuit patterns of two layers is short. CONSTITUTION:A first circuit pattern 2 composed of a copper foil is formed on the surface of an insulative board 1. A hole is formed from the rear side of the insulative board 1 by using a drill 4. A swelling part 2a is formed by swelling the copper foil in the part corresponding with the part with which the first circuit pattern 2 is connected, in the direction separating from the insulative board 1. An insulating layer 5 is formed on a circuit board 3 so as to expose the tip of the swelling part 2a. Finally a second circuit pattern 6 is formed on the insulating layer 5 so as to be in contact with the tip of the swelling part 2a, which constitutes an interlayer connection part for electrically connecting the first circuit pattern with the second circuit pattern.