Method of making printed wiringboards
AssigneeNippon Electric Co., Ltd.
InventorsMasashige Matsumoto, Hideaki Kobuna, Seiji Hiraide, Kouichi Kawai
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Abstract
A predetermined portion of a wiring substrate having wiring patterns obtained by etching a copper layer formed on an insulating substrated is covered with a plating resistant first insulating film, then a portion of lead patterns is covered by a removable and plating resistance second film. Then overplated coating is applied onto predetermined wiring patterns and thereafter the second film is removed. Thereafter only lead patterns are selectively etched off.
Claims7
A method of making a printed wiring board, comprising the steps of:
- preparing an insulating substrate by etching a conductive base pattern thereon, said base pattern consisting of circuit area and electroplating current supply area for electroplating the contact region of said circuit area;
- covering a first plating and etching resistant insulating film on said base pattern except for said contact region and said supply area;
- covering a second plating resistant film on said supply area;
- forming an overplated coating on said exposed contact region by supplying plating current thereto through said supply area;
- removing said second film while allowing said first film to remain intact;
- and
- selectively etching off only exposed portions of said conductive base pattern in said supply area.
A method of making a printed wiring board, comprising the steps of:
- preparing an insulating substrate by etching a conductive base pattern thereon, said base pattern including a first area to be overplated, a second area to be retained as a part of said printing wiring board, and a third area to be removed;
- covering a first plating and etching resistant insulating film on said second area;
- covering a second plating resistant film on said third area;
- forming an overplated coating on said first area by supplying plating current thereto through said third area;
- removing said second film while allowing said first film to remain intact;
- and
- selectively etching off said third area.
Dependencies are inferred from the claim text.