| 摘要 |
PURPOSE: To effectively prevent an organic insulating layer from separating from a metallic core by a method, wherein the organic insulating layer is formed on the metallic core with a protective metal plating layer, such as a nickel layer which protects the metallic core and a bonding reinforcing metal oxide layer therebetween. CONSTITUTION: The surface of an aluminum core 1 is covered with a nickel layer 3, which is a protective metal-plating layer. The surface of the nickel layer 3 is covered with a blackened copper layer 4, which is a bonding reinforcing metal oxide layer. An epoxy prepreg layer 5 which is an organic insulating layer is applied to the aluminum core 1 with the nickel layer 3 and the blackened copper later 4 therebetween. The copper layer 4, subjected to a blackening treatment which is one of the oxidation treatments has a needle structure and hence has an enlarged surface area and the bonding strength between the epoxy prepreg layer 5 and the aluminum core 1 is reinforced. In order to form the blackened copper layer 4, copper plating is applied and then the copper plating layer is subjected to the blackening treatment. |
