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:
Aug. 17, 2010
Filed:
Nov. 30, 2006
Edward A. Preble, Raleigh, NC (US);
Denis Tsvetkov, Morrisville, NC (US);
Andrew D. Hanser, Raleigh, NC (US);
N. Mark Williams, Raleigh, NC (US);
Xueping Xu, Stamford, CT (US);
Edward A. Preble, Raleigh, NC (US);
Denis Tsvetkov, Morrisville, NC (US);
Andrew D. Hanser, Raleigh, NC (US);
N. Mark Williams, Raleigh, NC (US);
Xueping Xu, Stamford, CT (US);
Kyma Technologies, Inc., Raleigh, NC (US);
Abstract
In a method for making an inclusion-free uniformly semi-insulating GaN crystal, an epitaxial nitride layer is deposited on a substrate. A 3D nucleation GaN layer is grown on the epitaxial nitride layer by HVPE under a substantially 3D growth mode, wherein a surface of the nucleation layer is substantially covered with pits and the aspect ratio of the pits is essentially the same. A GaN transitional layer is grown on the nucleation layer by HVPE under a condition that changes the growth mode from the substantially 3D growth mode to a substantially 2D growth mode. After growing the transitional layer, a surface of the transitional layer is substantially pit-free. A bulk GaN layer is grown on the transitional layer by HVPE. After growing the bulk layer, a surface of the bulk layer is smooth and substantially pit-free. The GaN is doped with a transition metal during at least one of the foregoing GaN growth steps.