Silicon wafers with stabilized oxygen precipitate nucleation centers and process for making the same

US6808781B2 · kind B2 · utility

Assignee

• MEMC Electronic Materials, Inc. · US

Inventors

• Luciano Mule'Stagno · Chesterfield, US
• Jeffrey L. Libbert · O'Fallon, US
• Richard J. Phillips · Saint Peters, US
• Milind Kulkarni · Chesterfield, US
• Mohsen Banan · University City, US
• Stephen J. Brunkhorst · Chesterfield, US

Key dates

• Filing date: Dec 23, 2002
• Grant date: Oct 26, 2004
• Expiry date: Dec 23, 2022

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/21
• WIPO field: Semiconductors
• WIPO sector: Electrical engineering

Abstract

A silicon wafer having a controlled oxygen precipitation behavior such that a denuded zone extending inward from the front surface and oxygen precipitates in the wafer bulk sufficient for intrinsic gettering purposes are ultimately formed. Specifically, prior to formation of the oxygen precipitates, the wafer bulk comprises dopant stabilized oxygen precipitate nucleation centers. The dopant is selected from a group consisting of nitrogen and carbon and the concentration of the dopant is sufficient to allow the oxygen precipitate nucleation centers to withstand thermal processing such as an epitaxial deposition process while maintaining the ability to dissolve any grown-in nucleation centers.