| abstract |
A copper electroplating bath useful in filling non-through holes formed on a substrate which contains a water-soluble copper salt, sulfuric acid, and chloride ions and further contains a brightener, a carrier, and a leveler as additives, wherein the leveler contains at least one water-soluble polymer containing quaternary nitrogen, tertiary nitrogen, or both which are cationizable in a solution. In the copper electroplating bath, the filling power for non-through holes formed on a substrate can be easily controlled so as to fit to the size of the holes only by changing the quaternary nitrogen to tertiary nitrogen ratio of the water-soluble polymer to be used as the leveler, which enables copper electroplating of non-through holes of various sizes with a good fit to the sizes. |