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. 07, 2017
Filed:
May. 20, 2014
Applicant:
Semiconductor Energy Laboratory Co., Ltd., Atsugi-shi, Kanagawa-ken, JP;
Inventors:
Assignee:
Semiconductor Energy Laboratory Co., Ltd., Atsugi-shi, Kanagawa-ken, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H01L 27/12 (2006.01); H01L 29/66 (2006.01);
U.S. Cl.
CPC ...
H01L 29/66765 (2013.01); H01L 27/1214 (2013.01); H01L 27/1288 (2013.01);
Abstract
To provide a manufacturing method of a highly reliable TFT, by which a more refined pattern can be formed through a process using four or three masks, and a semiconductor device. A channel-etched bottom gate TFT structure is adopted in which a photoresist is selectively exposed to light by rear surface exposure utilizing a gate wiring to form a desirably patterned photoresist, and further, a halftone mask or a gray-tone mask is used as a multi-tone mask. Further, a step of lifting off using a halftone mask or a gray-tone mask and a step of reflowing a photoresist are used.