Microlithographic projection exposure apparatus

Patent metadata

Field	Value
Publication number	US-9733395-B2
Application number	US-201113112357-A
Country	US
Kind code	B2
Filing date	May 20, 2011
Priority date	Sep 3, 2005
Publication date	Aug 15, 2017
Grant date	Aug 15, 2017

Abstract

The disclosure relates to a microlithographic projection exposure apparatus, such as are used for the production of large-scale integrated electrical circuits and other microstructured components. The disclosure relates in particular to coatings of optical elements in order to increase or reduce the reflectivity.

First claim

What is claimed is:

1. An optical system, comprising:
a plurality of optical elements; and
a plurality of antireflection coatings including a first antireflection coating and a second antireflection coating,
wherein:
each of the plurality of optical elements supports at least one of the plurality of antireflection coatings;
within a first incidence angle range, the first antireflection coating has a polarisation-dependent reflectivity which is greater for s-polarised light than for p-polarised light;
within a second incidence angle range, the second antireflection coating has a polarisation-dependent reflectivity which is less for s-polarised light than for p-polarised light;
the first and second antireflection coatings are arranged in a beam path of projection light so that their polarisation-dependent differences in reflectivity at least partially compensate each other;
the first antireflection coating is different from the second antireflection coating; and
the optical system is a microlithographic optical system.

2. The optical system of claim 1 , wherein the first and second antireflection coatings are arranged in the beam path of the projection light so that at least some light rays impinge on the first antireflection coating with incidence angles lying within the first incidence angle range, and also impinge on the second antireflection coating with incidence angles lying within the second incidence angle range.

3. The optical system of claim 1 , wherein the first incidence angle range is at least substantially identical to the second incidence angle range.

4. The optical system of claim 3 , wherein the first and second antireflection coatings are supported by the same optical element.

5. The optical system of claim 1 , wherein the first incidence angle range is different from the second incidence angle range.

6. The optical system of claim 5 , wherein the first antireflection coating is supported by a first optical element, and the second antireflection coating is supported by a second optical element.

7. The optical system of claim 1 , wherein the polarisation-dependent differences in reflectivity for the first and second antireflective coatings compensate each other so that a total transmission of the optical system does not depend on a state of polarisation of the projection light.

8. The optical system of claim 1 , further comprising:
a third antireflection coating configured so that, within a third incidence angle range, p-polarised light passes through the third antireflection coating with a retardation relative to s-polarised light; and
a fourth antireflection coating configured so that, within a fourth incidence angle range, s-polarised light passes through the fourth antireflection coating with a retardation relative to p-polarised light,
wherein the third and fourth antireflection coatings are arranged in the beam path of the projection light so that their polarisation-dependent phase differences at least partially compensate each other.

9. An apparatus, comprising:
the optical system of claim 1 ,
wherein the apparatus is a microlithographic projection exposure apparatus.

10. The optical system of claim 1 , wherein a portion of the first incidence angle range overlaps with a portion of the second incidence angle range.

11. An optical system, comprising:
a plurality of optical elements; and
a plurality of antireflection coatings including a first antireflection coating and a second antireflection coating,
wherein:
each optical element supports at least one of the plurality of antireflection coatings;
the first antireflection coating is configured so that, within a first incidence angle range, p-polarised light passes through the first antireflection coating with a retardation relative to s-polarised light;
the second antireflection coating is configured so that, within a second incidence angle range, s-polarised light passes through the second antireflection coating with a retardation relative to p-polarised light;
the first and second antireflection coatings are arranged in a beam path of projection light so that their polarisation-dependent retardation differences at least partially compensate each other; and
the optical system is a microlithographic optical system.

12. The optical system of claim 11 , wherein the first and second antireflection coatings are arranged in the beam path of the projection light so that at least some light rays impinge on the first antireflection coating with incidence angles lying within the first incidence angle range, and also impinge on the second antireflection coating with incidence angles lying within the second incidence angle range.

13. The optical system of claim 11 , wherein the first incidence angle range is at least substantially identical to the second incidence angle range.

14. The optical system of claim 13 , wherein the first and second antireflection coatings are supported by the same optical element.

15. The optical system of claim 11 , wherein the first incidence angle range is different from the second incidence angle range.

16. The optical system of claim 15 , wherein the first antireflection coating is supported by a first optical element, and the second antireflection coating is supported by a second optical element.

17. The optical system of claim 11 , wherein the polarisation-dependent differences in reflectivity for the first and second antireflective coatings compensate each other so that a total transmission of the optical system does not depend on a state of polarisation of the projection light.

18. An apparatus, comprising:
the optical system of claim 11 ,
wherein the apparatus is a microlithographic projection exposure apparatus.

19. The optical system of claim 11 , wherein a portion of the first incidence angle range overlaps with a portion of the second incidence angle range.

20. An optical system, comprising:
a plurality of optical elements; and
a plurality of antireflection coatings,
wherein:
each of the plurality of optical elements supports at least one of the plurality of antireflection coatings,
each antireflection coating has a polarisation-dependent reflectivity;
a combination of each of the plurality of antireflection coatings has a substantially polarisation-neutral reflectivity;
at least one of the plurality of antireflection coatings is different from another of the plurality of antireflection coatings; and
the optical system is a microlithographic optical system.

21. The optical system of claim 20 , wherein:
the plurality of antireflection coatings include first and second antireflection coatings;
within a first incidence angle range, the first antireflection coating has a polarisation-dependent reflectivity which is greater for s-polarised light than for p-polarised light;
within a second incidence angle range, the second antireflection coating has a reflectivity which is less for s-polarised light than for p-polarised light; and
the first and second antireflection coatings are arranged in a beam path of projection light so that their polarisation-dependent differences in reflectivity at least partially compensate each other.

22. The optical system of claim 21 , wherein a portion of the first incidence angle range overlaps with a portion of the second incidence angle range.

23. The optical system of claim 21 , wherein each antireflection coating has polarisation-dependent behaviour with respect to phase, and

Assignees

• Kamenov Vladimir
• Kraehmer Daniel
• Gruner Toralf
• Weissenrieder Karl-Stefan
• Feldmann Heiko
• Zirkel Achim
• Pazidis Alexandra
• Thome Bruno
• Six Stephan
• Zeiss Carl Smt Gmbh

Inventors

• Kamenov Vladimir
• Kraehmer Daniel
• Gruner Toralf
• Weissenrieder Karl-Stefan
• Feldmann Heiko
• Zirkel Achim
• Pazidis Alexandra
• Thome Bruno
• Six Stephan

Classifications

• G02B1/11 Primary

  Anti-reflection coatings · CPC title

• G03F7/70308

  Optical correction elements, filters or phase plates for manipulating imaging light, e.g. intensity, wavelength, polarisation, phase or image shift · CPC title

• G03F7/70958 Primary

  Optical materials or coatings, e.g. with particular transmittance, reflectance or anti-reflection properties · CPC title

• G03F7/70191 Primary

  Optical correction elements, filters or phase plates for controlling intensity, wavelength, polarisation, phase or the like · CPC title

• G03F7/70233

  Optical aspects of catoptric systems, i.e. comprising only reflective elements, e.g. extreme ultraviolet [EUV] projection systems · CPC title