Copper foil for high frequency circuit and method of production of same

Abstract

An electrodeposited copper foil having a rough surface having knob-like projections and a surface roughness of 2 to 4 μm at part of a surface thereof produced by electrolysis using an electrolyte containing copper as a main component and a compound having mercapto groups, at least one type of another organic compound, and chloride ions and an electrodeposited copper foil obtained by roughening treating an untreated copper foil having a matte side, for bonding with a resin substrate, having knob-like projections and a surface roughness of 2 to 4 μm by running a predetermined current through it for a predetermined time in an electroforming bath.

What is claimed is  
     
         1 . An electrodeposited copper foil wherein part of its surface comprises a rough surface having knob-like projections and a surface roughness of 2 to 4 μm.  
     
     
         2 . An electrodeposited copper foil as set forth in  claim 1 , wherein said rough surface having said knob-like projections and said surface roughness of 2 to 4 μm is a surface of an untreated copper foil for bonding with a resin substrate and is further roughening treated by running a predetermined current through the foil for a predetermined time in an electroforming bath.  
     
     
         3 . An electrodeposited copper foil as set forth in  claim 2 , wherein said electroforming bath is an acidic electroforming bath containing at least one of molybdenum, cobalt, nickel, iron, tungsten and arsenic.  
     
     
         4 . An electrodeposited copper foil as set forth in  claim 2  or  3 , wherein said rough surface is further formed with a copper plating layer.  
     
     
         5 . An electrodeposited copper foil as set forth in  claim 2  or  3 , wherein said rough surface is further formed with a copper plating layer and at least one layer of nickel plating, zinc plating, cobalt plating, plating of an alloy of the same and a chromate treatment layer on that, and according to need further formed with a coupling agent treatment layer.  
     
     
         6 . An electrodeposited copper foil as set forth in  claim 1 , wherein said rough surface having said knob-like projections and said surface roughness of 2 to 4 μm is a surface of an untreated copper foil for bonding with a resin substrate and is further formed with a copper plating layer and at least one layer of nickel plating, zinc plating, cobalt plating, plating of an alloy of the same and a chromate treatment layer on that, and according to need further formed with a coupling agent treatment layer.  
     
     
         7 . A method of producing an electrodeposited copper foil comprising electrolysis using an electrolyte containing copper as a main component and a compound having mercapto groups, at least one type of another organic compound, and chloride ions to form a copper foil wherein part of its surface comprises a rough surface having knob-like projections and a surface roughness of 2 to 4 μm.  
     
     
         8 . A method of producing an electrodeposited copper foil as set forth in  claim 7 , wherein an electroforming bath for a roughening treatment is an acidic electroforming bath containing at least one of molybdenum, cobalt, nickel, iron, tungsten and arsenic.  
     
     
         9 . A method of producing an electrodeposited copper foil comprising producing an electrodeposited copper foil having a matte side having a surface roughness of 2 to 4 μm using an electrolyte containing a compound having mercapto groups, at least one type of another organic compound, and chloride ions and roughening treating said matte side of said electrodeposited copper foil by running a predetermined current through it for a predetermined time in an electroforming bath.