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:
Nov. 30, 2021
Filed:
Sep. 13, 2019
Synopsys, Inc., Mountain View, CA (US);
Lawrence S. Melvin, III, Hillsboro, OR (US);
Yudhishthir P. Kandel, Durham, NC (US);
Synopsys, Inc., Mountain View, CA (US);
Abstract
Techniques and systems for improving wafer contrast by manipulating reflective extreme ultraviolet (EUV) mask absorber are described. Some embodiment disclosed herein provide for EUV absorber material, which transmits some EUV illumination, to suppress the printing of sub-resolution assist features (SRAFs) while making the SRAFs closer in size to the printed feature by thinning the SRAF absorber thickness from the nominal mask absorber thickness in the bright-field mask case. In the dark-field mask case, a layer of absorber material is left in the SRAF trenches to prevent SRAF printing.