Illumination optical unit for projection lithography

Patent metadata

Field	Value
Publication number	US-9507269-B2
Application number	US-201314135540-A
Country	US
Kind code	B2
Filing date	Dec 19, 2013
Priority date	Jul 11, 2011
Publication date	Nov 29, 2016
Grant date	Nov 29, 2016

Abstract

An illumination optical unit for projection lithography has a first polarization mirror device to reflect and polarize of illumination light. A second mirror device, which is disposed downstream of the polarization mirror device reflects an illumination light beam. At least one drive device is operatively connected to at least one of the two mirror devices. The two mirror devices are displaceable relative to one another via the drive device between a first relative position, which leads to a first beam geometry of the illumination light beam after reflection at the second mirror device, and a second relative position, which leads to a second beam geometry of the illumination light beam after reflection at the second mirror device, which is different from the first beam geometry. This results in a flexible predefinition of different illumination geometries, in particular of different illumination geometries with rotationally symmetrical illumination.

First claim

The invention claimed is:

1. An illumination optical unit, comprising:
a first mirror device configured to reflect and polarize light;
a second mirror device configured to reflect the light, the second mirror device being downstream of the first polarization mirror device along a path of the light through the illumination optical unit, the second mirror device comprising:
a ring-shaped outer mirror basic body in the form of a ring-shaped supporting frame; and
a plurality of mirror facets supported by the ring-shaped supporting frame; and

a drive device configured to cause relative displacement of the first and second mirror devices between first and second relative positions,
wherein:
in the first relative position, a beam of the light has a first geometry after reflecting from the second mirror device;
in the second relative position, the beam of the light has a second geometry after reflecting from the second mirror device;
the second geometry is different from the first beam geometry; and
the illumination optical unit is a projection lithography illumination optical unit.

2. The illumination optical unit of claim 1 , wherein the first mirror device comprises a conical mirror basic body.

3. The illumination optical unit of claim 2 , further comprising an active cooling device for the conical mirror basic body of the first mirror device.

4. The illumination optical unit of claim 3 , further comprising a coolant line comprising a spoke line which has a radial course component with respect to a rotational symmetry axis of the conical mirror basic body of the first mirror device.

5. The illumination optical unit of claim 4 , further comprising a coolant feed line via an axial line which runs along a rotational symmetry axis of the conical mirror basic body of the first mirror device.

6. The illumination optical unit of claim 3 , further comprising a coolant feed line via an axial line which runs along a rotational symmetry axis of the conical mirror basic body of the first mirror device.

7. The illumination optical unit of claim 2 , wherein the conical mirror basic body of the first mirror device in the form of a cone supporting frame having a conical basic shape, and the first mirror device comprises a plurality of mirror facets supported by the cone supporting frame.

8. The illumination optical unit of claim 7 , wherein at least some of the mirror facets of the first mirror device are tiltable about at least one tilting axis via assigned facet actuators.

9. The illumination optical unit of claim 8 , wherein the tilting axis lies in a plane containing the rotational symmetry axis of the cone supporting frame and runs parallel to a cone lateral surface of the basic shape of the cone supporting frame.

10. The illumination optical unit of claim 9 , wherein the tilting axis runs tangentially with respect to the rotational symmetry axis of the cone supporting frame and parallel to a cone base surface of the basic shape of the cone supporting frame.

11. The illumination optical unit of claim 8 , wherein the tilting axis runs tangentially with respect to the rotational symmetry axis of the cone supporting frame and parallel to a cone base surface of the basic shape of the cone supporting frame.

12. The illumination optical unit of claim 1 , wherein the outer mirror basic body comprises at least two ring supporting frames which are displaceable relative to one another along a ring rotational symmetry axis axially with the drive device.

13. An optical system, comprising:
an illumination optical unit according to claim 1 , the illumination field being configured to illuminate an object field; and
a projection optical unit configured to image the object field into an image field.

14. An apparatus, comprising:
an illumination system, comprising:
an EUV light source; and
an optical system an illumination optical unit according to claim 1 , the illumination field being configured to illuminate an object field; and

a projection optical unit configured to image the object field into an image field.

15. The apparatus of claim 14 , further comprising:
a first object holder configured to mount a first object arrangeable in the object field; and
a second object holder configured to mount a second object arrangeable in the image field.

16. An illumination optical unit, comprising:
a mirror device configured to reflect and polarize light, the polarization mirror device comprising:
a supporting frame having a conical basic shape; and
a plurality of mirror facets supported by the supporting frame,

wherein at least some of the mirror facets of the mirror device are tiltable about at least one tilting axis via assigned facet actuators, and the illumination optical tool is a projection lithography illumination optical tool.

17. The illumination optical unit of claim 16 , wherein the mirror device comprises a conical mirror basic body.

18. An optical system, comprising:
an illumination optical unit according to claim 16 , the illumination field being configured to illuminate an object field; and
a projection optical unit configured to image the object field into an image field.

19. An apparatus, comprising:
an illumination system, comprising:
an EUV light source; and
an optical system comprising an illumination optical unit according to claim 16 , the illumination field being configured to illuminate an object field; and

a projection optical unit configured to image the object field into an image field.

20. The apparatus of claim 19 , further comprising:
a first object holder configured to mount a first object arrangeable in the object field; and
a second object holder configured to mount a second object arrangeable in the image field.

21. An illumination optical unit, comprising:
a mirror device configured to reflect and polarize light,
wherein:
the mirror device comprising a ring-shaped outer mirror basic body in the form of a ring-shaped supporting frame; and the outer mirror basic body comprises at least two ring supporting frames which are displaceable relative to one another axially along a ring rotational symmetry axis.

22. The illumination optical unit of claim 21 , further comprising a drive device configured to displace the at least two ring supporting frames relative to one another axially along the ring rotational symmetry axis.

Assignees

• Zeiss Carl Smt Gmbh

Inventors

• Hennerkes Christoph
• Saenger Ingo
• Zimmermann Joerg
• Ruoff Johannes
• Meier Martin
• Schlesener Frank

Classifications

• G03F7/70891

  Temperature · CPC title

• G02B17/06

  using mirrors only {, i.e. having only one curved mirror (used in non-imaging applications G02B19/00)} · CPC title

• G03F7/70108 Primary

  Off-axis setting using a light-guiding element, e.g. diffractive optical elements [DOEs] or light guides · CPC title

• G02B7/1815

  with cooling or heating systems (cooling arrangements for laser mirrors H01S3/0401) · CPC title

• G03F7/70116

  Off-axis setting using a programmable means, e.g. liquid crystal display [LCD], digital micromirror device [DMD] or pupil facets · CPC title