Copper deposition from electroless plating bath
AssigneeInternational Business Machines Corporation
InventorsPeter A. Burnett, Dae Y. Jung, Ronald A. Kaschak, Roy H. Magnuson, Robert G. Rickert, Stephen L. Tisdale
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Abstract
Copper is deposited onto a substrate by plating a first layer of copper onto the substrate from an electroless plating bath and plating a second layer of copper onto the first layer of copper from a second and different electroless plating bath. The first and second plating baths differ from each other in at least the cyanide content. The process reduces plating void defects and reduces nodule formation.
Claims23
A process for plating copper onto a substrate that is catalytic for the deposition of copper thereon which comprises plating a first layer of copper onto said substrate from a first alkaline electroless copper plating bath containing up to about 2.3 ppm of cyanide ions and having an oxygen content of not less than about 2.5 ppm;
- plating a second layer of copper onto said first layer of copper from a second alkaline electroless copper plating bath containing about 5 to 11 ppm of cyanide ion and having an oxygen content of not less than 1.5 ppm below saturation.
Dependencies are inferred from the claim text.