The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 28, 1995
Filed:
Dec. 13, 1993
John A Edmond, Apex, NC (US);
Vladimir Dmitriev, Fuquay-Varina, NC (US);
Kenneth Irvine, Cary, NC (US);
Cree Research, Inc., Durham, NC (US);
Abstract
A transition crystal structure is disclosed for providing a good lattice and thermal match between a layer of single crystal silicon carbide and a layer of single crystal gallium nitride. The transition structure comprises a buffer formed of a first layer of gallium nitride and aluminum nitride, and a second layer of gallium nitride and aluminum nitride adjacent to the first layer. The mole percentage of aluminum nitride in the second layer is substantially different from the mole percentage of aluminum nitride in the first layer. A layer of single crystal gallium nitride is formed upon the second layer of gallium nitride. In preferred embodiments, the buffer further comprises an epitaxial layer of aluminum nitride upon a silicon carbide substrate.