| abstract |
A composite material (10) includes a structural carrier layer (12) and a relatively thin metal foil layer (14) separated by a release layer (16). The release layer (16), that may be an admixture of a metal such as nickel or chromium and a non-metal such as chromium oxide, nickel oxide, chromium phosphate or nickel phosphate, provides a separation force for the metal foil layer (14) from the carrier strip (12) that is typically on the order of 1.79 kg/m (0.1 pound per inch) to 35.7 kg/m (2 pounds per inch). This provides sufficient adhesion to prevent premature separation of the metal foil layer (14) from the carrier layer (12), but easy removal of the carrier layer (12) when desired. The metal foil layer (14) may be electrolytically formed copper having a low height profile, on the order of 0.5 micron to 2.7 microns, bond strength enhancing agent (20) coating a side (18) of the metal foil layer (14). The enhanced surface is subsequently bonded to a dielectric (22) and the carrier layer (12) then removed. <IMAGE> |