Patent ID: 9598787
Date: 2017-03-21
CPC Classifications: C23C,C25D,H05K

Claim:
1. A method consisting of: a) providing a substrate with a plurality of through-holes and a layer of copper flash on a surface of the substrate and walls of the plurality of through-holes; b) treating the substrate by applying an aqueous acid solution to at least the plurality of through-holes, the aqueous acid solution consisting of one or more inorganic acids, one or more reaction products of one or more aromatic heterocyclic nitrogen compounds and one or more epoxy-containing compounds, the one or more reaction products are in amounts of 1 ppm to 50 ppm, and water; c) providing an acid copper electroplating bath comprising one or more sources of copper ions, one or more acids, one or more brighteners and one or more levelers; d) immersing the treated substrate in the acid copper electroplating bath comprising one or more sources of copper ions, one or more acids, one or more brighteners and one or more levelers; and e) electroplating to at least fill the through-holes of the treated substrate with copper using the acid copper electroplating bath comprising one or more sources of copper ions, one or more acids, one or more brighteners and one or more levelers.