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:
Dec. 12, 2017
Filed:
Aug. 23, 2012
Akinori Koukitu, Tokyo, JP;
Yoshinao Kumagai, Tokyo, JP;
Toru Nagashima, Yamaguchi, JP;
Toru Kinoshita, Yamaguchi, JP;
Yuki Kubota, Yamaguchi, JP;
Rafael F. Dalmau, Raleigh, NC (US);
Jinqiao Xie, Allen, TX (US);
Baxter F. Moody, Raleigh, NC (US);
Raoul Schlesser, Raleigh, NC (US);
Zlatko Sitar, Apex, NC (US);
Akinori Koukitu, Tokyo, JP;
Yoshinao Kumagai, Tokyo, JP;
Toru Nagashima, Yamaguchi, JP;
Toru Kinoshita, Yamaguchi, JP;
Yuki Kubota, Yamaguchi, JP;
Rafael F. Dalmau, Raleigh, NC (US);
Jinqiao Xie, Allen, TX (US);
Baxter F. Moody, Raleigh, NC (US);
Raoul Schlesser, Raleigh, NC (US);
Zlatko Sitar, Apex, NC (US);
Hexatech, Inc., Morrisville, NC (US);
National University Corporation Tokyo University of Agriculture and Technology, Tokyo, JP;
Tokuyama Corporation, Yamaguchi, JP;
Abstract
The invention provides highly transparent single crystalline AlN layers as device substrates for light emitting diodes in order to improve the output and operational degradation of light emitting devices. The highly transparent single crystalline AlN layers have a refractive index in the a-axis direction in the range of 2.250 to 2.400 and an absorption coefficient less than or equal to 15 cm-1 at a wavelength of 265 nm. The invention also provides a method for growing highly transparent single crystalline AlN layers, the method including the steps of maintaining the amount of Al contained in wall deposits formed in a flow channel of a reactor at a level lower than or equal to 30% of the total amount of aluminum fed into the reactor, and maintaining the wall temperature in the flow channel at less than or equal to 1200° C.