Rohm & Haas Electronic Materials LLC

Nagarajan Jayaraju

Leon Barstad

Elie H Najjar

Zuhra I Niazimbetova

Joanna Dziewiszek

Leon R Barstad

Direct current plating methods inhibit void formation, reduce dimples and eliminate nodules. The method involves electroplating copper at a high current density followed by a pause in electroplating and then turning on the current to electroplate at a lower current density to fill through-holes.

Method of filling through-holes to reduce voids and other defects

Direct current plating methods inhibit void formation, reduce dimples and eliminate nodules. The method involves electroplating copper at a high current density followed by electroplating at a lower current density to fill through-holes.

Pulse plating methods which include a forward pulse but no reverse pulse inhibit or reduce dimpling and voids during copper electroplating of through-holes in substrates such as printed circuit boards. The pulse plating methods may be used to fill through-holes with copper where the through-holes are coated with electroless copper or flash copper.

Filling through-holes

The methods inhibit or reduce dimpling and voids during copper electroplating of through-holes with flash copper layers in substrates such as printed circuit boards. An acid solution containing reaction products of aromatic heterocyclic nitrogen compounds and epoxy-containing compounds is applied to the through-holes of the substrate followed by filling the through-holes with copper using a copper electroplating bath which includes additives such as brighteners and levelers.

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Framingham, MA, United States of America

Nagarajan Jayaraju