Electrolytic copper plating solution analyzer, and electrolytic copper plating solution analysis method

Patent metadata

Field	Value
Publication number	US-2016377573-A1
Application number	US-201615259734-A
Country	US
Kind code	A1
Filing date	Sep 8, 2016
Priority date	Mar 11, 2014
Publication date	Dec 29, 2016
Grant date	—

Abstract

An electrolytic copper plating solution analyzer comprises an analysis container for accommodating a part of an electrolytic copper plating solution containing additives including a promoter, an inhibitor and a leveler, a working electrode immersed in the electrolytic copper plating solution accommodated in the analysis container, a reference electrode immersed in the electrolytic copper plating solution and used as a reference when a potential of the working electrode is determined, a counter electrode immersed in the electrolytic copper plating solution, a rotation drive unit for rotating the working electrode at a given speed, a current generation unit passing an electric current with a given current density between the working electrode and the counter electrode, a potential measurement unit for measuring the potential between the working electrode and the reference electrode, and an analysis unit for analyzing the relationship between an elapsed time after the current passage and the potential.

First claim

What is claimed is:

1 . An electrolytic copper plating solution analyzer, comprising:
an analysis container for accommodating, as an analysis sample, a part of an electrolytic copper plating solution containing additives including a promoter, an inhibitor and a leveler; a working electrode immersed in the electrolytic copper plating solution accommodated in the analysis container and capable of receiving and transferring electrons; a reference electrode immersed in the electrolytic copper plating solution accommodated in the analysis container and used as a reference when a potential of the working electrode is determined; a counter electrode immersed in the electrolytic copper plating solution accommodated in the analysis container; a rotation drive unit capable of rotating the working electrode at a given speed; a current generation unit capable of passing an electric current with a given current density between the working electrode and the counter electrode; a potential measurement unit for measuring a potential between the working electrode and the reference electrode; and an analysis unit for analyzing the relation between a time elapsed after the current passage and the potential, wherein when the relation between the elapsed time and the potential is analyzed, the analysis unit calculates parameters indicating a condition of the electrolytic copper plating solution based on such a reaction mechanism that a Cu(I) species, which is generated on a surface of the working electrode during the course of the deposition reaction of a copper plated film and formed from a component of the promoter and a Cu(I) ion, is substituted for the inhibitor, which is located on the surface of the working electrode, as the deposition reaction of the copper plated film proceeds, the leveler is substituted for the Cu(I) species, which is located on the surface of the working electrode, as the deposition reaction of the copper plated film proceeds, and the Cu(I) species forms a complex at least with the promoter thereby showing a promotion function; and identifies the condition of the electrolytic copper plating solution by use of the parameters.

2 . The electrolytic copper plating analyzer of claim 1 , wherein the analysis unit analyzes the relation between the elapsed time and the potential, measured with the potential measurement unit, based on the following equations (1) to (4) to calculate i i , i a , i l , C a */T i and k 2 ·C l /T i as parameters

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Assignees

• Toppan Printing Co Ltd

Inventors

• Kosugi Masahiro
• Okubo Toshikazu

Classifications

• G01N27/4161

  measuring the voltage and using a constant current supply, e.g. chronopotentiometry · CPC title

• G01N27/423 Primary

  Coulometry · CPC title

• C25D3/58

  containing more than 50% by weight of copper · CPC title

• C25D3/12

  of nickel or cobalt · CPC title

• G01N27/42

  Measuring deposition or liberation of materials from an electrolyte; Coulometry, i.e. measuring coulomb-equivalent of material in an electrolyte · CPC title