| 摘要 |
PURPOSE:To obtain a multilayer printed circuit board with reduced haloing phenomena in through-hole plating, excellent heat resistance, adhesive property and high reliability by forming a copper oxide layer on the surface of an inner layer copper foil in an inner layer circuit board, electrically reducing copper oxide to metallic copper, forming a circuit pattern on the reduced inner layer copper foil and forming a thin copper oxide layer on the surface of the circuit pattern. CONSTITUTION:A glass cloth based epoxy resin copper sticked double-sided laminated sheet is used for an inner layer circuit board. A primary copper oxide layer is formed by dipping the inner layer circuit board in the aqueous solution of NaClO4, NaOH, Na2PO4 and 2H2O to form a primary copper oxide layer. Then, the primary copper oxide layer is reduced by conducting an electrolysis in an alkali aqueous solution. A circuit pattern is formed on the surface of reduced metallic copper by using a resin with UV-hardenability. Then, a secondary copper oxide layer is formed by dipping a copper sticked laminated sheet on which a circuit is formed in the aqueous solution of NaClO4, NaOH, Na2PO4 and 2H2O to be made an inner layer circuit board by applying baking thereto. |
