METHOD OF MANUFACTURING PRINTED WIRING BOARD EQUIPPED WITH VERY FINE WIRE PATTERN

• Main Authors: TAKE MORIO, IKEGUCHI NOBUYUKI, IWATA KEIICHI
• Format: Patent
• Language: English
• Published: 29.08.2003
• Edition: 7
• Subjects: APPARATUS THEREFOR; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; CHEMICAL SURFACE TREATMENT; CHEMISTRY; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATIONOR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; COATING MATERIAL WITH METALLIC MATERIAL; COATING METALLIC MATERIAL; DIFFUSION TREATMENT OF METALLIC MATERIAL; ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; ELECTROFORMING; ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION INGENERAL; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS; METALLURGY; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLICMATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASSC23 AND AT LEAST ONEPROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25; NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; PRINTED CIRCUITS; PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTIONOF COATINGS

PROBLEM TO BE SOLVED: To provide a high-density printed wiring board which is equipped with a very fine wire pattern excellent in adhesion to a copper foil and superior in shape. SOLUTION: A layer made of nickel and/or cobalt or an alloy of them is deposited as thick as 0.1 to 5 μm on the rugged mat surface of an electrolytic copper foil, the electrolytic copper foil mounted with the above layer is used as the copper foil, the copper foil is deposited as an outermost layer on a copper plated board, the electrolytic copper foil as the outermost layer is selectively removed by etching, a thin electroless plating copper layer and an electrolytic copper layer are provided to the residual layer of nickel metal, cobalt metal or an alloy layer of them, a pattern plating resist layer is deposited thereon, a pattern electrolytic copper plating process is carried out, the plating resist layer is removed, then the thin electroless plating copper layer and the electrolytic copper layer are selectively removed by dissolution, and then the layer of nickel metal, cobalt or an alloy of them is selectively removed by etching for the formation of the high-density printed wiring board. Therefore, the high-density wiring board which is equipped with the very fine wire pattern nearly having no undercut and excellent in adhesion to the copper foil can be obtained. COPYRIGHT: (C)2003,JPO