| abstract |
An object of the present invention is to provide an electrolytic copper plating method that ensures good film quality and via hole filling property with good reproducibility even for a substrate having a via hole, a resist, or the like during electroplating of a printed wiring board. Kind Code: A1 A pyridinium, bipyridinium, phenanthrolinium, quinolinium, and phenazinium are added to a plating solution used in electroplating a printed wiring board by adding an N-alkyl, N-aralkyl, or N-allyl group to onium. Add salt. [Selection diagram] Fig. 1 |