Microelectromechanical mirror assembly

Patent metadata

Field	Value
Publication number	US-10254654-B2
Application number	US-201715844086-A
Country	US
Kind code	B2
Filing date	Dec 15, 2017
Priority date	Aug 26, 2013
Publication date	Apr 9, 2019
Grant date	Apr 9, 2019

Abstract

An optical element assembly includes a base, and an element unit. The element unit includes (i) an optical element having an element central axis and an element perimeter; and (ii) an element connector assembly that couples the optical element to the base, the element connector assembly including a flexure assembly having an element flexure and a base flexure. A distal end of the element flexure is coupled to the optical element near the element perimeter, a distal end of the base flexure is coupled to the base, and a proximal end of the element flexure is coupled to a proximal end of the base flexure near the element central axis.

First claim

What is claimed is:

1. An optical element assembly for adjusting the characteristics of a beam, the optical element assembly comprising:
a base;
an optical element which the beam is incident thereon, the optical element including an element central axis;
a mover which moves the optical element in a move direction which crosses to a surface of the base;
a first flexure which is arranged between the optical element and the base, the first flexure extending in a first direction which crosses to the move direction, the first flexure having a first end which is connected to the optical element at a first position which is away from the element central axis of the optical element, and a second end which is located at a second position that is nearer to the element central axis of the optical element than the first position; and
a second flexure which is arranged between the optical element and the base, the second flexure extending in a second direction which crosses to the move direction, the second flexure having a third end which is connected to the optical element at a third position which is away from the element central axis of the optical element, and a fourth end which is located at a fourth position that is nearer to the element central axis of the optical element than the third position;
wherein the first end and the second end of the first flexure move different distances than one another when the optical element is moved in the move direction; and wherein the third end and the fourth end of the second flexure move different distances than one another when the optical element is moved in the move direction.

2. The optical element assembly of claim 1 , further comprising:
a third flexure which is arranged between the first flexure and the base, the third flexure extending in the first direction, the third flexure having a fifth end which is connected to the second end of the first flexure, and a sixth end which is connected to the base; and
a fourth flexure which is arranged between the second flexure and the base, the fourth flexure extending in the second direction, the fourth flexure having a seventh end which is connected to the fourth end of the second flexure, and an eighth end which is connected to the base.

3. The optical element assembly of claim 2 , wherein the sixth end of the third flexure is located farther away from the element central axis than the fifth end, and wherein the eighth end of the fourth flexure is located farther away from the element central axis than the seventh end.

4. The optical element assembly of claim 3 , further comprising:
a connector which connects the second end of the first flexure and the fifth end of the third flexure, and which connects the fourth end of the second flexure and the seventh end of the fourth flexure.

5. The optical element assembly of claim 4 , wherein the connector is located nearer to the element central axis of the optical element than the first position.

6. The optical element assembly of claim 3 , wherein the sixth end of the third flexure is connected to the base at a third position that is aligned with the first position along a first axis that is parallel to the move direction, and the eighth end of the fourth flexure is connected to the base at a fourth position that is aligned with the second position along a second axis that is parallel to the move direction.

7. The optical element assembly of claim 6 , further comprising:
a first connector which is arranged between the sixth end of the third flexure and the base, and which connects the sixth end and the base; and
a second connector which is arranged between the eighth end of the fourth flexure and the base, and which connects the eighth end and the base.

8. The optical element assembly of claim 1 , further comprising:
a first connector which is located at the first position, and which connects the first end and the optical element; and
a second connector which is located at the second position, and which connects the third end and the optical element.

9. The optical element assembly of claim 1 , wherein each of the first flexure and the second flexure extend from near the element central axis to near an outer perimeter of the optical element.

10. An exposure apparatus which exposes a workpiece with an exposure light, comprising:
the optical element assembly of claim 1 ;
an illumination optical system which illuminates the optical element of the optical element assembly with the exposure light;
a projection optical system which leads the exposure light from the optical element assembly to the workpiece and which projects a pattern on the workpiece; and
a controller configured to control a position of the optical element in the move direction.

11. A device manufacturing method comprising:
forming a pattern of photosensitive layer on the workpiece using the exposure apparatus of claim 10 ; and
processing the workpiece which has the pattern.

12. A method for adjusting the characteristics of a beam, the method comprising the steps of:
providing a base;
providing an optical element which the beam is incident thereon, the optical element including an element central axis;
arranging a first flexure between the optical element and the base, the first flexure extending in a first direction which crosses to the move direction, the first flexure having a first end which is connected to the optical element at a first position which is away from the element central axis of the optical element, and a second end which is located at a second position that is nearer to the element central axis of the optical element than the first position;
arranging a second flexure between the optical element and the base, the second flexure extending in a second direction which crosses to the move direction, the second flexure having a third end which is connected to the optical element at a third position which is away from the element central axis of the optical element, and a fourth end which is located at a fourth position that is nearer to the element central axis of the optical element than the third position; and
moving the optical element in a move direction which crosses to a surface of the base with a mover; wherein the first end and the second end of the first flexure move different distances than one another when the optical element is moved in the move direction; and wherein the third end and the fourth end of the second flexure move different distances than one another when the optical element is moved in the move direction.

13. The method of claim 12 , further comprising the steps of:
arranging a third flexure between the first flexure and the base, the third flexure extending in the first direction, the third flexure having a fifth end which is connected to the second end of the first flexure, and a sixth end which is connected to the base; and
arranging a fourth flexure between the second flexure and the base, the fourth flexure extending in the second direction, the fourth flexure having a seventh end which is connected to the fourth end of the second flexure, and an eighth end which is connected to the base.

14. The method of claim 13 , wherein the step of arranging a third flexure includes the third flexure being located farther away from the element central axis than the fifth end, and wherein the step of arranging the fourth flexure includes the eighth end of the fourth flexure being located farther away from the element central axis than the seventh end.

15. The method of claim 14 , further comprising the steps of:
connecting the second end of the first flexure and the fi

Assignees

• Nikon Corp

Inventors

• Palmer Shane R
• Binnard Michael

Classifications

• G03F7/70116

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

• G02B26/06 Primary

  for controlling the phase of light (G02B26/08 takes precedence {, measuring optical phase difference G01J9/00}) · CPC title

• G02B26/0841

  the reflecting element being moved or deformed by electrostatic means · CPC title

• G03F7/70075

  Homogenization of illumination intensity in the mask plane by using an integrator, e.g. fly's eye lens, facet mirror or glass rod, by using a diffusing optical element or by beam deflection · CPC title

• G03F7/70058 Primary

  Mask illumination systems · CPC title