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:
Jun. 02, 2026
Filed:
Jun. 17, 2021
Asml Netherlands B.v., Veldhoven, NL;
Derick Yun Chek Chong, 'S Hertogenbosch, NL;
Wouter Joep Engelen, Eindhoven, NL;
Vyacheslav Kachkanov, Steensel, NL;
Vahid Mohammadi, Eindhoven, NL;
Pieter Cristiaan De Groot, Heeze, NL;
ASML NETHERLANDS B.V., Veldhoven, NL;
Abstract
A transmissive diffraction grating for a phase-stepping measurement system for determining an aberration map for a projection system comprises an absorbing layer. The diffraction grating is for use with radiation having a first wavelength (for example (EUV radiation). The absorbing layer is provided with a two-dimensional array of through-apertures. The absorbing layer is formed from a material which has a refractive index for the radiation having the first wavelength in the range 0.% to 1.04.