| 摘要 |
A pattern plating method for fabricating printed circuit boards (10) begins by bonding (101) a thin layer (12) of copper (e.g., copper foil) to the surface of the board (10). A photoresist layer (14) is laminated over the copper layer (12), and then selectively exposed and developed to define a desired pattern of traces. A thick, second layer (15) of copper is deposited on the traces by electrolytic deposition (105), and the photoresist (14) is then removed. The board (10) is etched with a solution containing cupric chloride (or an ammoniacal etchant) to remove those portions of the first copper layer (12) that are not covered by the second copper layer (15). The present invention also allows through-holes (11) to be drilled (102) at selected locations after the first layer (12) of copper foil has been bonded to the board (10). A thin layer (13) of copper is then deposited by electroless deposition (103) to create a conductive surface in the through-holes (11) necessary for the subsequent step of electrolytic deposition (105) in the process above.
|
