公开(公告)号：US20250031294A1

公开(公告)日：2025-01-23

申请号：US18716468

申请日：2022-12-07

Applicant: ASML Netherlands B.V.

Inventor： Roger Anton Marie TIMMERMANS ,  Alexander Evgenevich LINKOV ,  Bas Willem Johannes Johanna Anna VAN DORP ,  Thomas William Georg KHOURI ,  Paul Peter Anna Antonius BROM

IPC: H05G2/00 ,  G01B11/27 ,  G02B5/00 ,  G03F7/00

Abstract: An aperture for detecting a laser beam misalignment, the aperture comprising: a body including a first opening and defining a first axis; a beam dump; an optical element including a second opening wherein the first opening and the second opening are coaxial with the first axis, the optical element being configured to redirect a misaligned laser beam to a detector or to split a misaligned laser beam into at least two sub-beams; a laser beam detection system configured to detect laser light, wherein the optical element is configured to direct a first sub-beam to the beam dump, and to direct a second sub-beam to the laser beam detection system. Also described is an aperture including an enclosure, a method of detecting misalignment of a laser beam, a radiation source comprising such an aperture, a lithographic apparatus comprising such a radiation source or aperture, and the use of the same in a lithographic apparatus or method.