Lithographic apparatus and pivotable structure assembly

• US 20080309901A1
• Filed: 06/15/2007
• Published: 12/18/2008
• Est. Priority Date: 06/15/2007
• Status: Active Grant

• Current Assignee: ASML Netherlands BV (ASML Holding NV)
• Original Assignee: ASML Netherlands BV (ASML Holding NV)
• Inventors: Peeters, Felix Godfried Peter, Rene Soemers, Hermanus Mathias Joannes
• Granted Patent: US 7,884,920 B2
• Time in Patent Office: Days
• US Class Current: 355/53
• CPC Class Codes: G02B 26/0858 the reflecting means being moved or deformed by piezoelectric means
• CPC Class Codes: G02B 26/105 with one or more pivoting mirrors or galvano-mirrors G02B26/101 takes precedence
• CPC Class Codes: G03F 7/702 Reflective illumination, i.e. reflective optical elements other than folding mirrors, e.g. extreme ultraviolet [EUV] illumination systems
• CPC Class Codes: G03F 7/70825 Mounting of individual elements, e.g. mounts, holders or supports workpiece or mask holders G03F7/707

Abstract

A mirror assembly to interact with a beam of radiation of a lithographic apparatus is disclosed. The mirror assembly includes a mirror, a piezo electric actuator, and a mover structure, the mover structure connected to the mirror, an assembly of the mirror and the mover structure being pivotable about a pivot point, the piezo electric actuator having a contacting surface to establish a slip-stick contact with the mover structure.

Claims

1. A lithographic apparatus comprising:

an illumination system configured to condition a radiation beam;

a support constructed to support a patterning device, the patterning device being capable of imparting the radiation beam with a pattern in its cross-section to form a patterned radiation beam;

a substrate table constructed to hold a substrate;

a projection system configured to project the patterned radiation beam onto a target portion of the substrate;

a mirror assembly to interact with the radiation beam, the mirror assembly comprising;

a mirror structure being pivotable about at least one axis and comprising a reflecting surface, and

an actuator to pivot the mirror structure, the actuator having a contacting surface to establish a slip-stick contact with a contacting part of the mirror structure.

2. The lithographic apparatus according to claim 1, wherein the actuator comprises a sheer piezo electric actuator to establish a movement of the contacting surface of the piezo electric actuator in a direction substantially in a plane parallel to the contacting surface.

3. The lithographic apparatus of claim 2, wherein the sheer piezo electric actuator comprises a dual layer sheer piezo electric actuator, each layer configured to establish movement of the contacting surface in a substantially orthogonal direction to the other layer.

4. The lithographic apparatus of claim 1, wherein the pivotability of the mirror structure is provided by the mirror structure being suspended in a diaphragm.

5. The lithographic apparatus of claim 4, wherein the diaphragm extends in a plane substantially parallel to the contacting surface.

6. The lithographic apparatus of claim 1, wherein a surface of the contacting part of the mirror structure is convex, a radius of the convex surface substantially corresponds to a distance between the surface of the contacting part and a pivot axis of the mirror structure.

7. The lithographic apparatus of claim 1, wherein the contacting surface of the actuator comprises a metallic layer.

8. The lithographic apparatus of claim 1, further comprising a spring to preload the mirror structure onto the contacting surface.

9. The lithographic apparatus of claim 1, comprising a plurality of mirror assemblies, the mirror structures of the mirror assemblies being arranged to form a mirror plane, each of the mirror structures pivotable by its respective actuator and positioned in an optical path of the radiation beam.

10. A pivotable structure assembly comprising:

a pivotable structure pivotable about at least one axis; and

an actuator to pivot the pivotable structure, the actuator having a contacting surface to establish a slip-stick contact with a contacting part of the pivotable structure.

11. The pivotable structure assembly of claim 10, wherein the actuator comprises a sheer piezo electric actuator to establish a movement of the contacting surface of the piezo electric actuator in a direction substantially in a plane parallel to the contacting surface.

12. The pivotable structure assembly of claim 11, wherein the sheer piezo electric actuator comprises a dual layer sheer piezo electric actuator, each layer configured to establish movement of the contacting surface in a substantially orthogonal direction to the other layer.

13. The pivotable structure assembly of claim 10, wherein the pivotability of the pivotable structure is provided by the pivotable structure being suspended in a diaphragm.

14. The pivotable structure assembly of claim 13, wherein the diaphragm extends in a plane substantially parallel to the contacting surface.

15. The pivotable structure assembly of claim 10, wherein a surface of the contacting part of the pivotable structure is convex, a radius of the convex surface substantially corresponds to a distance between the surface of the contacting part and a pivot axis of the pivotable structure.

16. The pivotable structure assembly of claim 10, wherein the contacting surface of the actuator comprises a metallic layer.

17. The pivotable structure assembly of claim 10, further comprising a spring to preload the pivotable structure onto the contacting surface.

18. The pivotable structure assembly of claim 10, wherein the pivotable structure comprises a mirror having a reflecting surface.

19. The pivotable structure assembly of claim 10, wherein the actuator comprises a piezo electric actuator.

20. A mirror assembly, comprising:

a mirror;

a mover structure connected to the mirror and pivotable about a pivot point; and

a piezo electric actuator having a contacting surface to establish a slip-stick contact with the mover structure.