| 摘要 |
PURPOSE:To prevent a plating solution for forming a plated layer in a through hole from reaching intermediate layer patterns by a method wherein copper foil layers, the respective surfaces of which are coated with resin layers, are each laminated and pressed on both surfaces of a substrate, on both surfaces of which the intermediate layer patterns are respectively formed, and thereafter, all the copper foil layers are etched and intermediate layers formed are pressed with surface layers through prepreg layers. CONSTITUTION:Members 15 obtainable by coating respectively B stage-state thermosetting resin layers 14 on the surfaces of copper foil layers 13 are each pressed and fixed by pressure on both surfaces of a substrate 11, on both surface of which intermediate layer patterns 12 and an intermediate layer land pattern 12A are respectively formed, while being heated. Then, the copper foil layers 13 on the pressed resin layers 14 are etched and removed with an etching liquid consisting of ferric chloride (FeCl3). By such a way, an intermediate layer 22 is formed from the substrate 11, which has the patterns 12 and whose both surfaces are coated with each layer 14. Then, prepreg layers 16 are each installed on the exposed layers 14 and moreover, surface layers 18, on each one surface of which copper foil patterns 17 are formed, are installed and these substrate 11, resin layers 14, prepreg layers 16, surface layers 18 and so forth on are pressed and laminated while being heated to form into a multilayer printed board. |
