Gold electroplating process
AssigneeBell Telephone Laboratories, Incorporated
InventorsYutaka Okinaka, Catherine Wolowodiuk
Life of this patent
Estimating the term…
Abstract
Certain reducible species are found in gold electroplating solutions which interfere with efficient electroplating of gold and make uncertain gold thickness predictions based on current throughput. A gold electroplating process is described which minimizes formation of undesirable reducible species. This process uses an anode of titanium having a coating of the oxides of ruthenium, iridium, rhodium, titanium or mixtures thereof. In addition, a procedure is described for removing such chemical species from the gold plating bath which does not adversely affect the gold electroplating solution.
Claims11
A process for electroplating gold on surfaces using:
- anode, surface to be plated as cathode, gold plating solution and an electrical source of energy comprising the step of activating the source of electrical energy so that current flows through the anode, the gold plating solution and the cathode;
- characterized in that the formation of gold III species is minimized by use of an anode structure which comprises a base made of titanium with metal oxide on the surface in which at least 25 percent by weight of the metal oxide is at least one oxide selected from the group consisting of ruthenium oxide, iridium oxide, rhodium oxide, and titanium oxide or mixtures thereof.
Dependencies are inferred from the claim text.