Detection of suppressor breakdown contaminants in a plating bath

US6749739B2 · kind B2 · utility

Assignee

• ECI TECHNOLOGY, INC.

Inventors

• Gene Chalyt · Hackettstown, US
• Peter Bratin · Great Neck, US
• Michael Pavlov · Kingston, US
• Alex Kogan · Carlstadt, US
• Michael James Perpich · Hackensack, US

Key dates

• Filing date: Oct 7, 2002
• Grant date: Jun 15, 2004
• Expiry date: Jan 1, 2023

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C25D21/12
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

Relative concentrations of active suppressor additive species and suppressor breakdown contaminants in an acid copper electroplating bath are determined by cyclic voltammetric stripping (CVS) dilution titration analysis using two negative electrode potential limits. The analysis results for the more negative potential limit provide a measure of the suppressor additive concentration alone since the suppressor breakdowvn contaminants are not effective at suppressing the copper deposition rate at the more negative potentials. The analysis results for the less negative potential limit provide a measure of the combined concentrations of the suppressor additive and the suppressor breakdown contaminants. Comparison of the results for the two analyses yields a measure of the concentration of the suppressor breakdown contaminants relative to the suppressor additive concentration.