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:
Oct. 12, 2021
Filed:
Apr. 03, 2019
Applicant:
Powerchip Semiconductor Manufacturing Corporation, Hsinchu, TW;
Inventors:
Hsiao-Chiang Lin, New Taipei, TW;
Yu-Hsuan Chang, Hsinchu County, TW;
Li-Chun Tseng, Yilan County, TW;
Assignee:
Powerchip Semiconductor Manufacturing Corporation, Hsinchu, TW;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G03F 7/20 (2006.01); G03F 1/38 (2012.01);
U.S. Cl.
CPC ...
G03F 7/70733 (2013.01); G03F 1/38 (2013.01); G03F 7/70875 (2013.01);
Abstract
A method for designing a photomask includes calculating an open ratio of an initial photomask to determine whether the open ratio of the initial photomask is less than 25%, and then changing a design of the initial photomask in response to determining the open ratio is less than 25%, such that a changed photomask has a reverse tone to the design of the initial photomask, and an open ratio of the changed photomask is 75% or more. The method can solve the issue caused by thermal expansion of the photomask.