Facet mirror device

Patent metadata

Field	Value
Publication number	US-9599910-B2
Application number	US-201313744943-A
Country	US
Kind code	B2
Filing date	Jan 18, 2013
Priority date	Jul 28, 2010
Publication date	Mar 21, 2017
Grant date	Mar 21, 2017

Abstract

A facet mirror device includes a facet element and a support element which supports the facet element. The facet element includes a curved support section. The support element includes a support section. The support section of the support element forms a support edge which contacts the curved support section of the facet element.

First claim

What is claimed is:

1. A facet mirror device, comprising:
a facet element including a curved section; and
a support element including a wall having a first surface and an end, the first surface defining a recess in the support element, a second surface of the support element being inclined with respect to the first surface and meeting the first surface at the end of the wall to provide a support edge,
wherein the support edge contacts the curved section in a contact region to support the facet element so that the facet element is tiltable relative to the support element.

2. The facet mirror device of claim 1 , wherein:
the contact region has a first curvature, and the support edge has a second curvature so that generally a line contact exists between the support edge and the facet element; and
at least one of the following holds:
the support edge includes at least one edge segment;
the support edge is a continuous ring shaped edge;
the wall confines a recess within the support element;-and
the curved section has a spherical surface in the contact region.

3. The facet mirror device of claim 1 , wherein at least one of the following holds:
the facet element is connected to the support element by an adhesive bond;
the facet element is connected to the support element via a bonding material located adjacent to the support edge;
the facet element is adhesively connected to the support element in a region between the support edge and the curved section; and
the facet element is glued, soldered, laser soldered, welded, laser welded and/or diffusion bonded to the support element.

4. The facet mirror device of claim 3 , wherein at least one of the following holds:
at least a majority of the bonding material is at a side of the support edge facing away from the recess; and
the bonding material seals a gap between the facet element and the support element.

5. The facet mirror device of claim 1 , wherein at least one of the following holds:
the support edge is a sharp edge defining a minimum edge radius of curvature less than 3 mm; and
a width of a manufacturing tolerance related gap between the support edge and the facet element is less than 10 μm.

6. The facet mirror device of claim 1 , wherein the facet element includes an at least partially reflective front surface and a rear surface, and the curved section is part of the rear surface,
and wherein at least one of the following holds:
the rear surface is substantially free from protrusions;
the curved section defines a continuously curved shell, and the rear surface is substantially free from protrusions protruding from the rear surface beyond the spherical shell;
the front surface of the facet element includes a reflective surface area adapted to be used in an orientation adjustment operation during mounting of the facet element to the support element; and
the front surface of the facet element has an outer contour that is section wise curved and/or section wise polygonal.

7. The facet mirror device of claim 1 , wherein at least one of the following holds:
the facet element comprises a material selected from the group consisting of silicon, silicon carbide, quartz, nickel plated copper and steel; and
the support element comprises a material selected from the group consisting of silicon carbide, silicon infiltrated silicon carbide and tungsten carbide.

8. The facet mirror device of claim 1 , wherein at least one of the following holds:
the wall confines a recess within the support element, the wall includes a connector section adapted to connect a suction mechanism to the recess to generate a negative pressure within the recess so that the negative pressure adjustably fixes the facet element relative to the support element during mounting of the facet element to the support element;
the support element includes at least one cooling duct; and
the wall confines a recess within the support element, the recess is filled with a cooling medium or a heat transfer medium.

9. The facet mirror device of claim 1 , wherein:
the facet mirror comprises a plurality of further facet elements, the support element includes a plurality of further support edges, and each of the further support edges supports a corresponding one of the plurality of further facet elements; or
the facet mirror device comprises a least 1000 facet elements, and the support element supports the at least 1000 facet elements.

10. The facet mirror device of claim 1 , wherein the second surface intersects the first surface of the wall to define, in a sectional plane extending transverse to the first surface of the wall, a vertex, and the support edge is at the vertex.

11. The facet mirror device of claim 1 , wherein a line contact exists between the support edge and the curved section.

12. An optical imaging arrangement, comprising:
an illumination unit adapted to illuminate a pattern of a mask; and
an optical projection unit adapted to transfer an image of the pattern onto a substrate,
wherein:
the illumination unit comprises a facet mirror device, and/or the optical projection unit comprises a facet mirror device; and

wherein the facet mirror device comprises:
a facet element including a curved section;
a support element including a support edge contacting the curved section in a contact region to support the facet element so that the facet element is tiltable relative to the support element;
the support edge is at an end of a wall of the support element; and
the support element has mutually inclined first and second surfaces meeting at the end of the wall to provide the support edge.

13. The optical imaging arrangement of claim 12 , wherein the second surface intersects the first surface of the wall to define, in a sectional plane extending transverse to the first surface of the wall, a vertex, and the support edge is at the vertex.

14. The optical imaging arrangement of claim 12 , wherein a line contact exists between the support edge and the curved section.

15. A method, comprising:
contacting a curved portion of a facet element with a support edge of a support element to provide a facet mirror device,
wherein:
the support edge is at an end of a wall of the support element;
the wall has a first surface which defines a recess in the support element;
a second surface of the support element is inclined with respect to the first surface and extends away from the end of the wall to provide the support edge; and
the support edge contacts the curved section to support the facet element so that the facet element is tiltable relative to the support element.

16. The method according to claim 15 , wherein at least one of the following holds:
the facet element is connected to the support element by an adhesive bond;
the facet element is connected to the support element via a bonding material located adjacent to the support edge;
the facet element is adhesively connected to the support element in a region of contact between the support edge and the curved portion; and
the facet element is connected to the support element by at least one bonding technique selected from the group consisting of gluing, soldering, laser soldering, welding, laser welding, diffusion bonding.

17. The method of claim 16 , wherein at least one of the following holds:
a majority of the bonding material is located at a side of the support edge facing away from the recess;
the bonding material seals a gap between the facet element and the support element; and
the recess is filled with a cooling medium or a heat transfer medium.

Assignees

• Zeiss Carl Smt Gmbh

Inventors

• Hartjes Joachim

Classifications

• G02B5/132

  with individual reflector mounting means · CPC title

• G02B7/1815

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

• G02B5/09

  Multifaceted or polygonal mirrors {, e.g. polygonal scanning mirrors; Fresnel mirrors} · CPC title

• G02B5/0891

  Ultraviolet [UV] mirrors (apparatus for microlithography exposure G03F7/70; X-ray multilayer structures G21K1/06) · CPC title

• Y10T29/49826

  Assembling or joining · CPC title