Process for the surface polishing of silicon wafers

US6530826B2 · kind B2 · utility

Assignee

• Wacker Siltronic Gesellschaft Fur Halbleitermaterialien AG · DE

Inventors

• Guido Wenski · Burghausen, DE
• Thomas Buschhardt · Burghausen, DE
• Heinrich Hennhofer · Tirschenreuth, DE
• Bruno Lichtenegger · Emmerting, DE

Key dates

• Filing date: Oct 30, 2001
• Grant date: Mar 11, 2003
• Expiry date: Oct 30, 2021

Classification

• Technology area (CPC H): Electricity
• CPC primary: H01L21/02024
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

A process for the surface polishing of a silicon wafer, includes the successive polishing of the silicon wafer on at least two different polishing plates covered with polishing cloth, with a continuous supply of alkaline polishing abrasive with SiO2 constituents, an amount of silicon removed during the polishing on a first polishing plate being significantly higher than on a second polishing plate, with the overall amount of silicon removed not exceeding 1.5 &mgr;m. A polishing abrasive (1a), then a mixture of a polishing abrasive (1b) and at least one alcohol, and finally ultrapure water (1c) are added to the first polishing plate, and a mixture of a polishing abrasive (2a) and at least one alcohol and then ultrapure water (2b) are added to the second plate.