公开(公告)号：US20210033979A1

公开(公告)日：2021-02-04

申请号：US16969078

申请日：2019-01-28

Applicant: ASML Netherlands B.V.

Inventor： Martijn Cornelis SCHAAFSMA ,  Mhamed AKHSSAY ,  James Robert DOWNES

IPC: G03F7/20

Abstract: A method of calibrating a projection system heating model to predict an aberration in a projection system in a lithographic apparatus, the method comprising passing exposure radiation through a projection system to expose one or more exposure fields on a substrate provided on a substrate table, making measurements of the aberration in the projection system caused by the exposure radiation, wherein the time period between measurements is less than the time period that would be taken to expose all exposure fields on the substrate.