| 摘要 |
A pattern plating method for fabricating printed circuit boards begins by bonding a thin layer of copper (e.g., copper foil) to the surface of the board. A photoresist layer is laminated over the copper layer, and then selectively exposed and developed to define a desired pattern of traces. A thick, second layer of copper is deposited on the traces by electrolytic deposition, and the photoresist is then removed. The board is etched with a solution containing cupric chloride (or an ammoniacal etchant) to remove those portions of the first copper layer that are not covered by the second copper layer. The present invention also allows through-holes to be drilled at selected locations after the first layer of copper foil has been bonded to the board. A thin layer of copper is then deposited by electroless deposition to create a conductive surface in the through-holes necessary for the subsequent step of electrolytic deposition in the process above.
|
