Fabrication of SiC substrates with low warp and bow

US8449671B2 · kind B2 · utility

Assignee

• II-VI Incorporated · US

Inventors

• Ping Wu · Hackettstown, US
• Ilya Zwieback · Township of Washington, US
• Avinesh K. Gupta · Berkeley Heights, US
• Edward Semenas · Allentown, US

Key dates

• Filing date: Jun 26, 2008
• Grant date: May 28, 2013
• Expiry date: Mar 31, 2030

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C30B33/02
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

A method of fabricating an SiC single crystal includes (a) physical vapor transport (PVT) growing a SiC single crystal on a seed crystal in the presence of a temperature gradient, wherein an early-to-grow portion of the SiC single crystal is at a lower temperature than a later-to-grow portion of the SiC single crystal. Once grown, the SiC single crystal is annealed in the presence of a reverse temperature gradient, wherein the later-to-grow portion of the SiC single crystal is at a lower temperature than the early-to-grow portion of the SiC single crystal.