| 摘要 |
PROBLEM TO BE SOLVED: To thin a board and to improve strength by forming etching resist on the copper foil of a specified copper-clad thermosetting resin adhesion film, selectively etching/removing the part of unnecessary copper foil and forming a fine opening part becoming a via hole. SOLUTION: A copper-clad thermosetting resin adhesion film 21 in which an adhesion layer comprising high molecular weight epoxy polymer which is obtained by blending and polymerizing bifunctional epoxy resin and halogenized bifunctional phenol so that epoxy group/phenol hydroxy group=1/0.9-1/1.1 and whose weight average molecular weight is not less than 100,000 is formed on copper foil is overlapped with an inner layer circuit board 1, vacuum press molding is executed and a copper-clad stacked board 4 with inner layer circuit is obtained. Etching resist 8 is formed on the surface of the outer layer copper foil and an opening part 51 is formed in a part where a via hole is formed. Thus, the via hole superior in mass production, connection reliability and an electric characteristic is provide. The board can be thinned and strength can be improved. |
