Patent · US Active

Test device and method for testing a mirror

US10422718B2 · kind B2 · utility

1Cited by

3References

18Claims

0Family size

Assignee

Carl Zeiss SMT GmbH · DE

Inventors

Hans-Michael Stiepan · Aalen, DE
Jochen Hetzler · Aalen, DE
Sebastian Fuchs · Aalen, DE

Key dates

Filing date	Aug 14, 2017
Grant date	Sep 24, 2019
Priority date	—
Expiry date	Nov 9, 2037

Classification

Technology area (CPC G)Physics
CPC primaryG03F7/706
WIPO fieldMeasurement
WIPO sectorInstruments

Abstract

A test appliance and a method for testing a mirror, e.g., a mirror of a microlithographic projection exposure apparatus. The test appliance has a computer-generated hologram (CGH), and a test can be carried out on at least a portion of the mirror by way of an interferometric superposition of a test wave that is directed onto the mirror by this computer-generated hologram and a reference wave. Here, the computer-generated hologram (CGH) (120, 320) is designed in such a way that, during operation of the appliance, it provides a first test wave for testing a first portion of the mirror (101, 301) by interferometric superposition with a reference wave in a first position of the mirror (101, 301) and at least a second test wave for testing a second portion of the mirror (101, 301) by interferometric superposition with a reference wave in a second position of the mirror (101, 301).

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.