Large aluminum nitride crystals with reduced defects and methods of making them

US8349077B2 · kind B2 · utility

Assignee

• CRYSTAL IS, INC. · US

Inventors

• Robert T. Bondokov · Watervliet, US
• Kenneth E. Morgan · New York, US
• Glen A. Slack · Scotia, US
• Leo J. Schowalter · Latham, US

Key dates

• Filing date: Nov 28, 2006
• Grant date: Jan 8, 2013
• Expiry date: Jul 11, 2029

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/21
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

Reducing the microvoid (MV) density in AlN ameliorates numerous problems related to cracking during crystal growth, etch pit generation during the polishing, reduction of the optical transparency in an AlN wafer, and, possibly, growth pit formation during epitaxial growth of AlN and/or AlGaN. This facilitates practical crystal production strategies and the formation of large, bulk AlN crystals with low defect densities—e.g., a dislocation density below 104 cm−2 and an inclusion density below 104 cm−3 and/or a MV density below 104 cm−3.