To improve the durability of a printed-circuit board and other electronic packaging devices, by bringing the wall part of the aperture of a resin being located on an electronic device substrate into contact with a swelling agent and an etching agent composition whose pH is equal to or less than a specific value while they do not contain any hydroxide constituents before plating.
Copper layers 12a and 12b are formed at both the outsides of a substrate 10, a through hole 16 is formed between the copper layers 12a and 12b, and the copper layers 12a and 12b are electrically interconnected. Before plating the surface of the through hole 16, the insulation wall of a resin where apertures are exposed is treated by a swelling agent and an etching agent solution that has a pH of 13 or less and essentially do not contain any hydroxide constituents such as NaOH or KOH. Then, the conditions of the through hole 16 and the apertures are prepared for plating, thus improving the durability of a printed-circuit board and other electronic packaging devices.
KOBAYASHI TAKAHIRO
KONDO MASAKI
BAYES MARTIN W
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