Mirror arrangement for an EUV projection exposure apparatus, method for operating the same, and EUV projection exposure apparatus

Patent metadata

Field	Value
Publication number	US-9709770-B2
Application number	US-201414584164-A
Country	US
Kind code	B2
Filing date	Dec 29, 2014
Priority date	Jul 24, 2012
Publication date	Jul 18, 2017
Grant date	Jul 18, 2017

Abstract

A mirror arrangement for an EUV projection exposure apparatus for microlithography comprises a plurality of mirrors each having a layer which is reflective in the EUV spectral range and to which EUV radiation can be applied, and having a main body. In this case, at least one mirror of the plurality of mirrors has at least one layer comprising a material having a negative coefficient of thermal expansion. Moreover, a method for operating the mirror arrangement and a projection exposure apparatus are described. At least one heat source is arranged, in order to locally apply heat in a targeted manner to the at least one layer having a negative coefficient of thermal expansion of the at least one mirror.

First claim

The invention claimed is:

1. An arrangement, comprising:
a plurality of mirrors comprising a first mirror, each of the plurality of mirrors comprising:
a surface that is reflective in the EUV spectral range; and
a main body; and

a first heat source,
wherein:
the first mirror further comprises a layer comprising a material having a negative coefficient of thermal expansion;
the first heat source is configured to apply heat to the layer comprising the material having the negative coefficient of thermal expansion; and
the first heat source is configured to apply a positionally variable heat distribution to the layer comprising the material having the negative coefficient of thermal expansion.

2. The arrangement of claim 1 , wherein:
the first mirror further comprises:
a thermally insulating layer; and
a layer comprising a material having a positive coefficient of thermal expansion; and

the thermally insulating layer separates the layer comprising the material having the positive coefficient of thermal expansion from the layer comprising the material having the negative coefficient of thermal expansion.

3. The arrangement of claim 2 , wherein the material having the positive coefficient of thermal expansion comprises at least one material selected from the group consisting of Zr, Y, Nb, Mo, Si, Ge, Ru, RuO2, RuSi, Ni.

4. The arrangement of claim 2 , further comprising a second heat source, wherein the second heat source is configured to apply heat to the layer comprising the material having the positive coefficient of thermal expansion.

5. The arrangement of claim 1 , wherein the plurality of mirrors comprises a second mirror which is different from the first mirror, and the second mirror comprises a layer comprising a material having a negative coefficient of thermal expansion.

6. The arrangement of claim 5 , wherein:
during use of the arrangement, EUV radiation passes through the arrangement along a path; and
the first and second mirrors are arranged at positions in the path that are conjugate or approximately conjugate with regard to their optical effect.

7. The arrangement of claim 5 , further comprising a second heat source, wherein the second heat source is configured to apply heat to a layer of the second mirror.

8. The arrangement of claim 1 , wherein the plurality of mirrors comprises a second mirror which is different from the first mirror, and the second mirror comprises a layer comprising a material having a positive coefficient of thermal expansion.

9. The arrangement of claim 1 , wherein the first heat source is configured to apply heat to the layer comprising the material having the negative coefficient of thermal expansion from a side of the main body of the first mirror.

10. An arrangement, comprising:
a plurality of mirrors comprising a first mirror, each of the plurality of mirrors comprising:
a surface that is reflective in the EUV spectral range; and
a main body; and

a first heat source,
wherein:
the first mirror further comprises a layer comprising a material having a negative coefficient of thermal expansion;
the first heat source is configured to apply heat to the layer comprising the material having the negative coefficient of thermal expansion; and
the first heat source comprises an IR radiation source.

11. An arrangement, comprising:
a plurality of mirrors comprising a first mirror, each of the plurality of mirrors comprising:
a surface that is reflective in the EUV spectral range; and
a main body; and

a first heat source,
wherein:
the first mirror further comprises a layer comprising a material having a negative coefficient of thermal expansion;
the first heat source is configured to apply heat to the layer comprising the material having the negative coefficient of thermal expansion; and
the first heat source is configured to apply heat to the layer comprising the material having the negative coefficient of thermal expansion through the reflective layer of the first mirror.

12. The arrangement of claim 11 , wherein the first mirror further comprises a thermally insulating layer which is between the main body of the first mirror and the layer comprising the material having the negative coefficient of thermal expansion.

13. The arrangement of claim 12 , wherein the first mirror further comprises a layer having high thermal conductivity which is between the thermally insulating layer and the main body of the first mirror.

14. An arrangement, comprising:
a plurality of mirrors comprising a first mirror, each of the plurality of mirrors comprising:
a surface that is reflective in the EUV spectral range; and
a main body; and

a first heat source,
wherein:
the first mirror further comprises a layer comprising a material having a negative coefficient of thermal expansion;
the first heat source is configured to apply heat to the layer comprising the material having the negative coefficient of thermal expansion; and
the material having the negative coefficient of expansion comprises at least one material selected from the group consisting of ZrMo 2 O 8 , ZrW 2 O 8 , HfMo 2 O 8 , Zr 2 (MoO 4 ) 3 , Zr 2 (WO 4 ) 3 , Hf 2 (MoO 4 ) 3 , ScF 3 , ZnC 2 N 2 , ZnF 2 , Y 2 W 2 O 12 , BiNiO 3 .

Assignees

• Zeiss Carl Smt Gmbh

Inventors

• Bittner Boris
• Wabra Norbert
• Schneider Sonja
• Schoemer Ricarda
• Wagner Hendrik
• Iliew Rumen
• Pauls Walter

Classifications

• G02B7/008

  with means for compensating for changes in temperature or for controlling the temperature; thermal stabilisation · CPC title

• G03F7/706

  Aberration measurement · CPC title

• G03F7/70266 Primary

  Adaptive optics, e.g. deformable optical elements for wavefront control, e.g. for aberration adjustment or correction · CPC title

• G03F7/70891

  Temperature · CPC title

• G21K2201/067

  Construction details · CPC title