Copper foil for high frequency circuit, method of production and apparatus for production of same, and high frequency circuit using copper foil

Abstract

A copper foil reducing transmission loss at a high frequency and excellent in bond strength with a resin substrate, including at least a granular layer and a columnar layer in its thickness direction, the columnar layer being formed on at least one surface of the granular layer forming the copper foil or the granular layer being formed on at least one surface of the columnar layer forming the copper foil, the relation of the thickness A of the granular layer and the thickness B of the columnar layer in the copper foil being preferably A/(A+B)=40 to 99%, a method of production and apparatus for production for the same, and a high frequency circuit using the same.

1 . A method of production of a copper foil for a high frequency circuit comprising immersing and rotating a foil-making drum in an electrolytic tank to form a columnar layer on the surface of said foil-making drum, then plating a granular layer on at least one surface of the same.  
   
   
       2 . A high frequency circuit fabricated using a copper foil produced by a method of production as set forth in  claim 1.