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. 07, 2015
Filed:
Jan. 23, 2014
Semiconductor Energy Laboratory Co., Ltd., Atsugi-shi, Kanagawa-ken, JP;
Yoshiaki Yamamoto, Tokyo, JP;
Koichi Ito, Kanagawa, JP;
Motomu Kurata, Kanagawa, JP;
Taiga Muraoka, Kanagawa, JP;
Daigo Ito, Kanagawa, JP;
Semiconductor Energy Laboratory Co., Ltd., Atsugi-shi, Kanagawa-ken, JP;
Abstract
When an oxide semiconductor film is microfabricated to have an island shape, with the use of a hard mask, unevenness of an end portion of the oxide semiconductor film can be suppressed. Specifically, a hard mask is formed over the oxide semiconductor film, a resist is formed over the hard mask, light exposure is performed to form a resist mask, the hard mask is processed using the resist mask as a mask, the oxide semiconductor film is processed using the processed hard mask as a mask, the resist mask and the processed hard mask are removed, a source electrode and a drain electrode are formed in contact with the processed oxide semiconductor film, a gate insulating film is formed over the source electrode and the drain electrode, and a gate electrode is formed over the gate insulating film, the gate electrode overlapping with the oxide semiconductor film.