| 摘要 |
PURPOSE:To manufacture a multilayer printed wiring board wherein hollowing resistance is excellent, the adhesion and acid resistance are not decreased, and the drill workability is superior by a method wherein an oxide film layer of copper is formed by blackening an inner layer board surface where conductor circuits are formed, with aqueous solution of sodium hydroxide, a part of the oxide film layer is dissolved with sulfuric acid, and then prepreg is overlapped on the inner layer board. CONSTITUTION:An inner layer board, on the surface of which copper conductor circuit is formed, is used. For example, the inner layer board of surface and rear, or the inner layer boards of 4 layers, 6 layers, 8 layers and 10 layers wherein circuits are formed in the inner layer can be used. Aqueous solution of sodium hydroxide of concentration of 10-50g/l is used as blackening solution. Sodium chloride, sodium phosphate, etc., are added to the aqueous solution of sodium hydroxide. On the inner layer board surface in which circuits are formed in the above manner, an oxide film is formed. Then sulfuric acid dipping is performed, and a part of the oxide film is dissolved by dipping the board in normal sulfuric acid of concentration of 1/30-1/10. Prepreg and an outer layer copper foil are overlapped on the inner layer board obtained by the above manner, and a multilayer printed board is manufactured by an ordinary method. |
