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:
Mar. 17, 2026
Filed:
Sep. 01, 2022
Taiwan Semiconductor Manufacturing Company, Ltd., Hsinchu, TW;
Ping-Hsun Lin, New Taipei City, TW;
Chien-Cheng Chen, Hsinchu County, TW;
Shih Ju Huang, New Taipei City, TW;
Pei-Cheng Hsu, Taipei City, TW;
Ta-Cheng Lien, Hsinchu County, TW;
Hsin-Chang Lee, Hsinchu County, TW;
TAIWAN SEMICONDUCTOR MANUFACTURING COMPANY, LTD., Hsinchu, TW;
Abstract
A method includes forming a test pattern and a reference pattern in an absorption layer of a photomask structure. The test pattern has a first trench and a second trench, the reference pattern has a third trench and a fourth trench, the test pattern and the reference pattern have substantially the same dimension in a top view, and the second trench is deeper than the first trench, the third trench, and the fourth trench. The method further includes emitting a light beam to the test pattern to obtain a first interference pattern reflected from the test pattern, emitting the light beam to the reference pattern to obtain a second interference pattern reflected from the reference pattern; and comparing the first interference pattern with the second interference pattern to obtain a measured complex refractive index of the absorption layer.