FORMING METHOD FOR CIRCUIT

• Main Authors: KAWAMOTO MINEO, TOBA RITSUJI, MURAKAMI KANJI
• Format: Patent
• Language: English
• Published: 18.01.1989
• Subjects: APPARATUS THEREFOR; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; CHEMISTRY; ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR; ELECTRICITY; ELECTROFORMING; ELECTROLYTIC OR ELECTROPHORETIC PROCESSES; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS; METALLURGY; PRINTED CIRCUITS; PROCESSES FOR THE ELECTROLYTIC OR ELECTROPHORETIC PRODUCTIONOF COATINGS

PURPOSE:To stick a plating resist fast to a foundation metallic layer sufficiently, to prevent peeling during plating, to obviate an adverse effect on a plating film and to form a fine circuit by shaping a second metallic layer onto the surface of the foundation metallic layer forming the plating resist. CONSTITUTION:A hole 3 is bored at the required position of an insulation plate 1 with a metallic layer 2, and a metallic thin-film 4 is shaped onto the metallic layer 2. A second metallic layer 5 is formed onto the metallic thin-film 4 or the metallic layer 2. A metal having an ionization tendency larger than a metal for pattern plating used in a postprocess or a metal from which an oxide is difficult to be produced is proper to a metal forming the second metallic layer 5. Sections except a desired circuit forming section are masked with a plating resist 6. A circuit is formed through pattern plating 7. Circuits up to the last can be formed through a conventional method. Accordingly, the plating resist is not peeled from a foundation metallic layer on pattern plating, thus acquiring a sufficient effect for shaping a fine circuit.