Reflective optical element

Patent metadata

Field	Value
Publication number	US-10338476-B2
Application number	US-201816011019-A
Country	US
Kind code	B2
Filing date	Jun 18, 2018
Priority date	Dec 16, 2015
Publication date	Jul 2, 2019
Grant date	Jul 2, 2019

Abstract

A reflective optical element, in particular for a microlithographic projection exposure apparatus or a mask inspection apparatus. According to one aspect, the reflective optical element has an optically effective surface, a substrate ( 405, 505 ), a reflection layer system ( 410, 510 ) and at least one porous outgassing layer ( 450, 550 ), which at least intermittently releases particles adsorbed in the outgassing layer ( 450, 550 ) when the optically effective surface ( 400 a, 500 a ) is irradiated by electromagnetic radiation.

First claim

What is claimed is:

1. A reflective optical element, comprising:
an optically effective surface;
a substrate;
a reflection layer system; and
at least one porous outgassing layer, which at least intermittently releases particles adsorbed in the outgassing layer when the optically effective surface is irradiated by electromagnetic radiation, and which is arranged on a side of the reflection layer system facing the substrate.

2. An optical apparatus, comprising at least one of a microlithographic projection exposure apparatus or a mask inspection apparatus, wherein the at least one apparatus comprises a reflective optical element as claimed in claim 1 .

3. The reflective optical element as claimed in claim 1 , wherein the outgassing layer has a first porous outgassing layer and a second porous outgassing layer configured to at least intermittently adsorb particles released by the first outgassing layer when the optically effective surface is irradiated by electromagnetic radiation.

4. The reflective optical element as claimed in claim 1 , further comprising at least one heat radiation layer, wherein, in comparison with an analogously structured reflective optical element without the heat radiation layer, the reflective optical element increases a radiation of heat induced by the electromagnetic radiation in the reflective optical element when the optically effective surface is irradiated by electromagnetic radiation.

5. The reflective optical element as claimed in claim 4 , wherein the heat radiation layer is arranged on a side of the reflection layer system facing the substrate.

6. The reflective optical element as claimed in claim 4 , wherein the heat radiation layer is arranged on a side of the reflection layer system facing the optically effective surface.

7. The reflective optical element as claimed in claim 1 , configured as a mirror.

8. An optical system comprising at least one reflective optical element as claimed in claim 1 .

9. The optical system as claimed in claim 8 , further comprising a heat sink arranged on a side of the substrate facing away from the reflection layer system.

10. The optical system as claimed in claim 8 , configured as a microlithographic projection exposure apparatus.

11. The optical system as claimed in claim 8 , configured as an optical system of a mask inspection apparatus.

12. A microlithographic projection exposure apparatus comprising an illumination device and a projection lens, wherein the projection exposure apparatus has a reflective optical element as claimed in claim 1 .

13. A mask inspection apparatus comprising an illumination device and an inspection lens, wherein the mask inspection apparatus comprises a reflective optical element as claimed in claim 1 .

14. A reflective optical element, comprising:
an optically effective surface;
a substrate; and
a multilayer system applied directly to the substrate, wherein the multilayer system comprises a reflection layer system and a Peltier element arranged between the substrate and the reflection layer system, wherein the Peltier element is configured to heat the reflection layer system while cooling the substrate.

15. The reflective optical element as claimed in claim 14 , wherein the multilayer system further comprises further comprising a heat buffer layer arranged between the substrate and the reflection layer system.

16. The reflective optical element as claimed in claim 14 , configured for an operating wavelength of less than 30 nm.

17. A reflective optical element, comprising:
an optically effective surface;
a substrate;
a reflection layer system; and
at least one heat radiation layer, wherein, in comparison with an analogously structured reflective optical element without the heat radiation layer, the reflective optical element increases a radiation of heat induced by the electromagnetic radiation in the reflective optical element when the optically effective surface is irradiated by electromagnetic radiation, and wherein the heat radiation layer is arranged on a side of the reflection layer system facing the optically effective surface.

18. An optical apparatus, comprising at least one of a microlithographic projection exposure apparatus or a mask inspection apparatus, wherein the at least one apparatus comprises a reflective optical element as claimed in claim 17 .

19. The reflective optical element as claimed in claim 17 , further comprising a heat insulation layer arranged between the substrate and the reflection layer system.

20. The reflective optical element as claimed in claim 19 , wherein the heat insulation layer comprises quartz.

21. The reflective optical element as claimed in claim 17 , further comprising a Peltier element arranged between the substrate and the reflection layer system.

Assignees

• Zeiss Carl Smt Gmbh

Inventors

• Huber Peter

Classifications

• G21K2201/065

  provided with cooling means · CPC title

• G03F1/84

  Inspecting · CPC title

• G21K1/062

  Devices having a multilayer structure · CPC title

• G03F7/70316

  Details of optical elements, e.g. of Bragg reflectors, extreme ultraviolet [EUV] multilayer or bilayer mirrors or diffractive optical elements · CPC title

• G03F7/70891

  Temperature · CPC title