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:
Jan. 23, 2024
Filed:
Mar. 17, 2022
Renesas Electronics Corporation, Tokyo, JP;
Shu Shimizu, Tokyo, JP;
RENESAS ELECTRONICS CORPORATION, Tokyo, JP;
Abstract
A non-volatile semiconductor memory and three or more types of transistors are provided. A thickness of a first gate oxide film of a first transistor is larger than that of a second gate oxide film of a second transistor, and is smaller than that of a third gate oxide film of a third transistor. In a first transistor region, a first silicon oxide film is formed on a surface of a semiconductor substrate, and second and third silicon oxide films are formed on the first silicon oxide film. By removing the second and third silicon oxide films and a part of an upper layer of the first silicon oxide film, the first gate oxide film is formed from the first silicon oxide film.