| 摘要 |
A product useful in the manufacture of printed circuits includes a carrier layer of copper having a thickness on the order of about 10-15 microns. A thin layer of copper having a thickness in the range of 1-12 microns, and which will provide the conductive path for the printed circuit, is secured to the copper carrier by an intermediate metallic layer positioned therebetween and secured to both layers of copper. The intermediate layer has a thickness in the range of 0.1-2.0 microns and is selected from the group consisting of nickel, a nickel-tin alloy, a nickel-iron alloy, lead and a tin-lead alloy. The intermediate layer adheres sufficiently to the thin layer of copper to prevent removal thereof during the etching process which removes the carrier layer of copper. The described thin metallic foil is bonded upon opposite sides of a suitable dielectric which may be a reinforced or non-reinforced epoxy or any one of a number of other suitable materials for forming the core of a printed circuit board. The core in fact may be formed of one or more printed circuits previously formed to provide what is known in the trade as a multilayer printed circuit board. The process for manufacture of a printed circuit board includes the steps of removing at least the copper carrier and in many applications the intermediate metallic layer protecting the thin layer of copper attached to the dielectric and formation of a circuit using the thin copper layer.
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