Mitsui Minings & Melting Co., Ltd.

Yoshikazu Akashi

Tatsuo Kataoka

Yutaka Iguchi

A process for producing a printed wiring board comprises the steps of depositing a base metal on at least one surface of an insulating film to form a base metal layer and further depositing copper or a copper alloy to form a conductive metal layer, then removing a surface metal layer, which is formed through the above step, by etching to form a wiring pattern, and then treating the base metal layer with a treating liquid capable of dissolving and/or passivating the metal that forms the base metal layer. The printed wiring board so provided comprises an insulating film and a wiring pattern formed on at least one surface of the insulating film, the wiring pattern including a base metal layer deposited on the insulating film surface and a conductive metal layer, the base metal layer for forming the wiring pattern protrudes in a widthwise direction more than the conductive metal layer for forming the wiring pattern.

Method for producing a printed circuit board

A printed wiring board manufacturing process comprises forming a conductive metal layer on at least one surface of an insulating film with a sputtered metal layer in between, selectively etching the conductive metal layer and the sputtered metal layer to produce a wiring pattern, treating the laminated film with a first treatment liquid capable of dissolving nickel of the sputtered metal layer, and treating with a second treatment liquid capable of dissolving chrome of the sputtered metal layer and also capable of eliminating the sputtered metal layer in the insulating film to remove a superficial surface of the insulating film exposed from the wiring pattern together with the residual sputtered metals in the superficial surface. A printed wiring board comprises an insulating film and a wiring pattern, wherein the insulating film in an area exposed from the wiring pattern has a thickness smaller by 1 to 100 nm than that of an area under the wiring pattern. The process eliminates the sputtered metals combined with the insulating film together with the superficial surface of the insulating film, and therefore the insulating film surface between wires does not contain any residual metals and a short circuit between wires is prevented.

Printed wiring board, its manufacturing method, and circuit device

A film carrier tape for mounting electronic components or devices that excels in not only migration resistance but also adhesiveness of wiring to insulating film; and a process for producing the same. The film carrier tape for mounting electronic components or devices has seed layer comprising a zinc layer superimposed on a treated surface of insulating film and a nickel base metal layer superimposed on a surface of a zinc layer, or comprising a layer of alloy containing elemental nickel and elemental zinc in specified proportion, superimposed on a treated surface of insulating film). In the film carrier tape for mounting electronic components or devices, at least part of a region extending across a width of wiring from an edge side thereof to the treated surface of the insulating film may be continuously covered with a zinc coating layer comprising elemental zinc.

Growing community of inventors

Ageo, Japan

Yoshikazu Akashi