C.uyemura Co., Ltd.

Koji Shimizu

Shinji Tachibana

Naoyuki Omura

Toshihisa Isono

Tomohiro Kawase

Kazuyoshi Nishimoto

Shunsaku Hoshi

For use for a circuit board where a through hole and a blind via hole co-exist, an electrolytic copper plating bath in which the covering power for the through hole and the plugging performance for the blind via hole are sufficient, and an electroplating method that uses the electrolytic copper plating bath, are disclosed. The electrolytic copper plating bath is mainly composed of a water-soluble copper salt, sulfuric acid and chloride ions. A polyamide polyamine, obtained on processing by heating of an epichlorohydrin modified product of a polycondensation product of diethylene triamine, adipic acid and &#x3b5;-caprolactam, is contained in the bath as a leveler.

Electrolytic copper plating bath and method for electroplating using the electrolytic copper plating bath

Disclosed is a method for a repeated electroplating of a workpiece to be plated as a cathode by using an insoluble anode in a plating vessel accommodating a copper sulfate plating bath, wherein a copper dissolution vessel different from the plating vessel is provided, the plating bath is transferred to the copper dissolution vessel and is returned from the copper dissolution vessel to the plating vessel for circulating the plating bath between the plating vessel and the copper dissolution vessel, copper ion supplying salt is charged into the copper dissolution vessel and dissolved in the plating bath so that copper ions consumed by the plating can be replenished, and the workpiece to be plated is continuously electroplated, characterized in that the plating bath is permitted to transfer between the anode side and the cathode side, and the plating bath is returned to vicinity of the anode in the return of the plating bath from the copper dissolution vessel to the plating vessel. Plating performance impairing components, which are produced when the copper ion supplying salt is dissolved in the plating bath for replenishing the copper ions, are oxidized and decomposed, whereby defective plating due to the presence of the plating performance impairing components can be prevented.

Continuous copper electroplating method

A continuous copper electroplating method wherein copper is continuously plated on a workpiece to be placed in a plating vessel accommodating a copper sulfate plating bath containing organic additives by use of a soluble or insoluble anode and a workpiece as a cathode, the method including overflowing the plating bath from the plating vessel in an overflow vessel under which the plating bath in the overflow vessel is returned to the plating vessel, providing an oxidative decomposition vessel, and returning a plating bath from the oxidative decomposition vessel through the overflow vessel to the plating vessel to circulate the plating bath between the plating vessel and oxidative decomposition vessel, and metallic copper is immersed in the plating bath in the oxidative decomposition vessel and exposed to air bubbling, so that decomposed/degenerated organic products formed by decomposition or degeneration produced during the copper electroplating can be oxidatively decomposed.

Disclosed herein is an electrolytic copper plating process for electroplating copper on workpieces in a copper sulfate plating bath filled in a plating tank and containing an organic additive while using a soluble anode or insoluble anode as an anode and the workpieces as cathodes, including the steps of, setting a bath current density at not higher than 5 A/L, immersing metal copper in a region of the copper sulfate plating bath, the region being apart from a region between the anode and the cathode and also from regions adjacent the anode and cathode, respectively, such that a neighborhood of the thus-immersed metal copper can be used as an oxidative decomposition region, setting an immersed area of the metal copper at not smaller than 0.001 dm/L based on the plating bath, and applying air bubbling to the oxidative decomposition region at not lower than 0.01 L/dm&#xb7;min based on the immersed area.

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Hirakata, Japan

Koji Shimizu