Dislocation distribution for silicon carbide crystalline materials

US11519098B2 · kind B2 · utility

Assignee

• Wolfspeed, Inc. · US

Inventors

• Yuri Khlebnikov · Raleigh, US
• Robert Tyler Leonard · Raleigh, US
• Elif Balkas · Cary, US
• Steven Griffiths · Ellicott City, US
• Valeri F. Tsvetkov · Durham, US
• Michael James Paisley · Garner, US

Key dates

• Filing date: Jan 29, 2020
• Grant date: Dec 6, 2022
• Expiry date: Jan 11, 2041

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C30B23/02
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

Silicon carbide (SiC) wafers, SiC boules, and related methods are disclosed that provide improved dislocation distributions. SiC boules are provided that demonstrate reduced dislocation densities and improved dislocation uniformity across longer boule lengths. Corresponding SiC wafers include reduced total dislocation density (TDD) values and improved TDD radial uniformity. Growth conditions for SiC crystalline materials include providing source materials in oversaturated quantities where amounts of the source materials present during growth are significantly higher than what would typically be required. Such SiC crystalline materials and related methods are suitable for providing large diameter SiC boules and corresponding SiC wafers with improved crystalline quality.