COMPOSITE COPPER FOIL, METHOD FOR PRODUCTION THEREOF AND HIGH FREQUENCY TRANSMISSION CIRCUIT USING SAID COMPOSITE COPPER FOIL

摘要

A composite copper foil which comprises a copper foil and, provided on at least one surface thereof, a smooth layer made of copper and/or silver; a method for producing a composite copper foil, which comprises rolling an ingot of a copper alloy into a foil having a desired thickness, and providing a smooth plating layer of copper and/or silver on at least one surface of the rolled copper alloy foil, or which comprises rolling an ingot of a copper alloy into a foil having a thickness of an intermediate size, providing a smooth plating layer of copper and/or silver on at least one surface of the rolled copper alloy foil, and then rolling the resultant copper alloy foil into a foil having a desired thickness, or and then subjecting the resultant copper alloy foil to a heat treatment or to a heat treatment and a rolling, to prepare a foil having a copper and/or silver plating layer of a thickness of at least 0.01 mum or more; and a high frequency transmission circuit having been formed by using the above composite copper foil or a composite copper foil produced by the above method. The composite copper foil can be suitably used for a high frequency transmission circuit being excellent in electroconductivity and in the form of its surface and having high strength, and the like.