US 12,405,108 B2
Production method and measurement method
Hans Michael Stiepan, Aalen (DE); Thomas Monz, Schlierbach (DE); Julian Kaller, Koenigsbronn (DE); and Ulrich Loering, Ulm (DE)
Assigned to CARL ZEISS SMT GMBH, Oberkochen (DE)
Filed by Carl Zeiss SMT GmbH, Oberkochen (DE)
Filed on Apr. 6, 2023, as Appl. No. 18/296,733.
Application 18/296,733 is a continuation of application No. PCT/EP2020/078193, filed on Oct. 8, 2020.
Prior Publication US 2023/0243644 A1, Aug. 3, 2023
Int. Cl. G01B 11/24 (2006.01); G01B 9/02 (2022.01); G01B 9/02055 (2022.01); G01M 11/00 (2006.01); G02B 5/08 (2006.01); G02B 7/18 (2021.01); G03F 7/00 (2006.01)
CPC G01B 11/2441 (2013.01) [G01B 9/02039 (2013.01); G01B 9/02076 (2013.01); G01M 11/005 (2013.01); G02B 5/0891 (2013.01); G02B 7/1815 (2013.01); G03F 7/70891 (2013.01); G02B 2207/101 (2013.01)] 13 Claims
OG exemplary drawing
 
1. A method for measuring a surface shape of an optical element in a predetermined measurement environment, wherein the optical element comprises a main body with a substrate and a reflective surface, and wherein at least one cooling channel for receiving a coolant is formed in the substrate,
the method comprising:
a) recording a cooling channel pressure,
b) recording a measurement environment pressure,
c) determining an actual pressure difference based on the cooling channel pressure and the measurement environment pressure,
d) comparing the actual pressure difference with a predetermined target pressure difference,
e) monitoring for a deviation between the actual pressure difference and the target pressure difference, wherein, if a deviation greater than a predetermined limit value is detected, the cooling channel pressure is adapted in such a way that the deviation becomes less than or equal to the predetermined limit value, and
f) measuring the surface shape if the deviation is less than or equal to the predetermined limit value.