| 摘要 |
PURPOSE: To obtain a multilayer printed-wiring board in which a hole can be worked by a chemical treatment by a method wherein copper-clad insulating sheets for outer layers are heated and laminated on one face or both faces of an inner-layer panel, holes are made in surface copper foils, a substratum resin composition is dissolved by an alkali, through holes are made again, the resin composition is hardened and wiring patterns are formed on the copper foils. CONSTITUTION: Copper-clad insulating sheets 2, for outer layers, on which second resin-composition layers 5 are to be formed are heated and laminated on one face or both faces of a copper wiring pattern 1 as an inner-layer panel. Positions corresponding to through holes 9 in the copper wiring pattern 1 are etched, and holes 8 are made in copper foils. A third resin composition 4' which is exposed by the holes 8 and a second resin composition 5 under it are dissolved by an alkali aqueous solution, through holes 9 are made again, and the respective resin compositions 4', 5 are hardened. Then, a conductive substance is formed in the through holes 9, and wiring patterns 1 are formed on the surface copper foils. Thereby, the holes can be worked by a chemical treatment, and a high-density interconnection can be realized. |
