Rolled Copper Foil or Electrolytic Copper Foil for Electronic Circuit, and Method of Forming Electronic Circuit using same

Abstract

A rolled copper foil or electrolytic copper foil for an electronic circuit to be used for forming a circuit by etching, characterized in comprising a layer of metal of one or more types among a platinum group, gold and silver with an etching rate that is lower than the copper formed on an etching surface side of the rolled copper foil or the electrolytic copper foil, or alternatively comprising a layer of an alloy having the above-described metal as its main component. This invention aims to achieve the following upon forming a circuit by etching a copper foil of a copper clad laminate; specifically, to prevent sagging caused by the etching; to form a uniform circuit of the intended circuit width; to shorten the time of forming a circuit by etching as much as possible; to improve the etching properties in pattern etching; and to prevent the occurrence of short circuits and defects in the circuit width.

Dependencies are inferred from the claim text.