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:
Sep. 20, 2016
Filed:
Dec. 15, 2014
Semiconductor Energy Laboratory Co., Ltd., Atsugi-shi, Kanagawa-ken, JP;
Shunpei Yamazaki, Tokyo, JP;
Naoto Yamade, Kanagawa, JP;
Yoshitaka Yamamoto, Nara, JP;
Hideomi Suzawa, Kanagawa, JP;
Masayuki Sakakura, Kanagawa, JP;
Yuhei Sato, Kanagawa, JP;
Yasumasa Yamane, Kanagawa, JP;
Semiconductor Energy Laboratory Co., Ltd., Atsugi-shi, Kanagawa-ken, JP;
Abstract
The semiconductor device is manufactured by the following method. A first oxide semiconductor film is formed over a first gate electrode and a first insulating film, oxygen is added to the first oxide semiconductor film, and then a second oxide semiconductor film is formed over the first oxide semiconductor film. Then, heat treatment is performed. Next, part of the first insulating film, part of the first oxide semiconductor film, and part of the second oxide semiconductor film are etched to form a first gate insulating film having a projection. Next, a pair of electrodes is formed over the second oxide semiconductor film, and a third oxide semiconductor film is formed over the second oxide semiconductor film and the pair of electrodes. Then, a second gate insulating film is formed over the third oxide semiconductor film, and a second gate electrode is formed over the second gate insulating film.