Control of electrolyte composition in a copper electroplating apparatus

US8128791B1 · kind B1 · utility

Assignee

• Novellus Systems, Inc. · US

Inventors

• Bryan L. Buckalew · Tualatin, US
• Jonathan D. Reid · Sherwood, US
• John Sukamto · Lake Oswego, US
• Zhian He · Beaverton, US
• Seshasayee Varadarajan · Lake Oswego, US
• Steven T. Mayer · Lake Oswego, US

Key dates

• Filing date: Oct 30, 2006
• Grant date: Mar 6, 2012
• Expiry date: Aug 3, 2029

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C25D17/002
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

In a copper electroplating apparatus having separate anolyte and catholyte portions, the concentration of anolyte components (e.g., acid or copper salt) is controlled by providing a diluent to the recirculating anolyte. The dosing of the diluent can be controlled by the user and can follow a pre-determined schedule. For example, the schedule may specify the diluent dosing parameters, so as to prevent precipitation of copper salt in the anolyte. Thus, precipitation-induced anode passivation can be minimized.