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. 05, 2019
Filed:
Dec. 14, 2017
Renesas Electronics Corporation, Tokyo, JP;
Renesas Electronics Corporation, Koutou-ku, Tokyo, JP;
Abstract
A mesa portion of a semiconductor device, which includes a channel base layer formed of a first nitride semiconductor layer, a channel layer formed of a second nitride semiconductor layer, a barrier layer formed of a third nitride semiconductor layer, a mesa-type fourth nitride semiconductor layer, a gate insulating film that covers the mesa portion, and a gate electrode formed over the gate insulating film, is used as a co-doped layer. The mesa portion is used as the co-doped layer, so that interface charges generated at an interface between the gate insulating film and the mesa portion can be cancelled by p-type impurity or n-type impurity in the co-doped layer and a threshold potential can be improved. Further, the fourth nitride semiconductor layer is n-type until the gate insulating film is formed, and the fourth nitride semiconductor layer is made neutral or p-type after the gate insulating film is formed.