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:
Jul. 29, 2014
Filed:
Oct. 20, 2011
Chi-ming Chen, Zhubei, TW;
Po-chun Liu, Hsinchu, TW;
Hung-ta Lin, Hsinchu, TW;
Chin-cheng Chang, New Taipei, TW;
Chung-yi Yu, Hsinchu, TW;
Chia-shiung Tsai, Hsinchu, TW;
Ho-yung David Hwang, Hsinchu, TW;
Chi-Ming Chen, Zhubei, TW;
Po-Chun Liu, Hsinchu, TW;
Hung-Ta Lin, Hsinchu, TW;
Chin-Cheng Chang, New Taipei, TW;
Chung-Yi Yu, Hsinchu, TW;
Chia-Shiung Tsai, Hsinchu, TW;
Ho-Yung David Hwang, Hsinchu, TW;
Abstract
A circuit structure includes a substrate, a nucleation layer of undoped aluminum nitride, a graded buffer layer comprising aluminum, gallium, nitrogen, one of silicon and oxygen, and a p-type conductivity dopant, a ungraded buffer layer comprising gallium, nitrogen, one of silicon and oxygen, and a p-type conductivity dopant without aluminum, and a bulk layer of undoped gallium nitride over the ungraded buffer layer. The various dopants in the graded buffer layer and the ungraded buffer layer increases resistivity and results in layers having an intrinsically balanced conductivity.