公开(公告)号：US20250164895A1

公开(公告)日：2025-05-22

申请号：US18514874

申请日：2023-11-20

Applicant: KLA Corporation

Inventor： Rajeev Rajendran ,  Michael Xie ,  Farid Atry ,  Florian Melsheimer ,  Rui-Fang Shi

IPC: G03F7/00 ,  H01L21/67

Abstract: A substrate is mounted on a chuck in a chamber of an EUV tool. An illumination aperture in the chamber provides a beam of light to illuminate the substrate on the chuck. The beam of light includes extreme ultraviolet (EUV) in-band (IB) light and out-of-band (OOB) light. The OOB light has longer wavelengths than the EUV IB light. A beam-narrowing aperture in the chamber, which is switchable into and out of a path for the beam of light, selectively narrows the beam of light to illuminate the substrate. A band-selection filter filters out the OOB light or the EUV IB light. Imaging optics in the chamber relay light from the substrate to an imaging plane. A grating spectrally disperses the light from the substrate. A sensor detects the light from the substrate as relayed by the imaging optics and spectrally dispersed by the grating.