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:
Mar. 08, 2022
Filed:
Aug. 05, 2020
Applicant:
Fuji Electric Co., Ltd., Kanagawa, JP;
Inventor:
Tsuyoshi Araoka, Fukushima, JP;
Assignee:
FUJI ELECTRIC CO., LTD., Kanagawa, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L 29/16 (2006.01); H01L 21/82 (2006.01); H01L 29/08 (2006.01); H01L 29/417 (2006.01); H01L 29/78 (2006.01); H01L 29/66 (2006.01);
U.S. Cl.
CPC ...
H01L 29/1608 (2013.01); H01L 29/086 (2013.01); H01L 29/41766 (2013.01); H01L 29/66068 (2013.01); H01L 29/7802 (2013.01);
Abstract
A silicon carbide semiconductor device includes a gate insulating film and a gate electrode made of ppolysilicon doped with boron at a high concentration. Among boron impurities contained in the polysilicon of the gate electrode,B, which is one of the isotopes of boron, is contained 90% or more, thereby reducing the amount ofB diffusing from the polysilicon of the gate electrode into the gate insulating film. This results in a suppression of a threshold voltage shift that occurs when AC voltage is applied to the gate electrode.