Mirror assembly with heat transfer mechanism

Patent metadata

Field	Value
Publication number	US-10371920-B2
Application number	US-201314387130-A
Country	US
Kind code	B2
Filing date	Mar 7, 2013
Priority date	Mar 22, 2012
Publication date	Aug 6, 2019
Grant date	Aug 6, 2019

Abstract

A mirror assembly (32) for directing a beam (28) includes a base (450), and an optical element (454) that includes (i) a mirror (460), (ii) a stage (462) that retains the mirror (460), (iii) a mover assembly (464) that moves the stage (462) and the mirror (460) relative to the base (450), and (v) a thermally conductive medium (466) that is positioned between the stage (462) and the base (450) to transfer heat between the stage (462) and the base (450). The thermally conductive medium (466) has a thermal conductivity that is greater than the thermal conductivity of air. The thermally conductive medium (466) can include an ionic fluid or a liquid metal.

First claim

What is claimed is:

1. An optical element assembly for directing a beam, the optical element assembly comprising:
a base including a plurality of recesses; and
a plurality of elements, each of the plurality of elements including (i) an optical element, (ii) a stage that retains the optical element, the stage including a transfer region that is sized and shaped to fit within one of the plurality of recesses with a gap therebetween, and a connector region that is connected to and extends between the optical element and the transfer region such that the transfer region is rigidly connected to the optical element, (iii) a mover assembly that is coupled to the optical element, the mover assembly moving the optical element and the stage about a first axis and about a second axis that is orthogonal to the first axis relative to the base while maintaining the transfer region spaced apart the gap from the base, the mover assembly being secured in direct contact with the connector region between the optical element and the transfer region, and (iv) a thermally conductive medium positioned within the gap between the transfer region and the base to transfer heat from the transfer region to the base so that heat transferred with the thermally conductive medium does not cause thermal distortion of the mover assembly;
wherein the optical elements are arranged in a patterned array such that the optical elements are adjacent to one another and are positioned in approximately the same plane.

2. The optical element assembly of claim 1 wherein the patterned array of optical elements is substantially circle-shaped.

3. The optical element assembly of claim 1 wherein each optical element includes at least one of (i) a mirror; (ii) a reflective surface; or (iii) a lens.

4. The optical element assembly of claim 1 wherein for at least one of the plurality of elements the mover assembly includes (i) a first axis movement assembly that moves the optical element about the first axis, the first axis movement assembly including a first flexure so that movement of the optical element about the first axis with the first axis movement assembly is decoupled from the movement of the optical element about the second axis; and (ii) a second axis movement assembly that moves the optical element about the second axis, the second axis movement assembly including a second flexure so that movement of the optical element about the second axis with the second axis movement assembly is decoupled from the movement of the optical element about the first axis.

5. The optical element assembly of claim 1 wherein for each of the plurality of elements the mover assembly includes (i) a first axis movement assembly that moves the optical element about the first axis, the first axis movement assembly including a first flexure so that movement of the optical element about the first axis with the first axis movement assembly is decoupled from the movement of the optical element about the second axis; and (ii) a second axis movement assembly that moves the optical element about the second axis, the second axis movement assembly including a second flexure so that movement of the optical element about the second axis with the second axis movement assembly is decoupled from the movement of the optical element about the first axis.

6. The optical element assembly of claim 5 wherein the mover assembly moves the optical element to move approximately about a movement point that is near a center of a reflective surface of the optical element.

7. An optical element assembly for directing a beam, the optical element assembly comprising:
a base including a plurality of recesses; and
a plurality of elements, each of the plurality of elements including (i) an optical element, (ii) a stage that retains the optical element, the stage including a transfer region that is sized and shaped to fit within one of the plurality of recesses with a gap therebetween, and a connector region that is connected to and extends between the optical element and the transfer region such that the transfer region is rigidly connected to the optical element, (iii) a mover assembly that is coupled to the optical element, the mover assembly moving the optical element and the stage about a first axis and about a second axis that is orthogonal to the first axis relative to the base while maintaining the transfer region spaced apart the gap from the base, the mover assembly being secured to the connector region between the optical element and the transfer region, the mover assembly moving the optical element to move approximately about a movement point that is near a center of a reflective surface of the optical element, and (iv) a thermally conductive medium positioned within the gap between the transfer region and the base to transfer heat from the transfer region to the base so that heat transferred with the thermally conductive medium does not cause thermal distortion of the mover assembly;
wherein the optical elements are arranged in a patterned array such that the optical elements are adjacent to one another and are positioned in approximately the same plane;
wherein for each of the plurality of elements the mover assembly includes (i) a first axis movement assembly that moves the optical element about the first axis, the first axis movement assembly including a first flexure so that movement of the optical element about the first axis with the first axis movement assembly is decoupled from the movement of the optical element about the second axis; and (ii) a second axis movement assembly that moves the optical element about the second axis, the second axis movement assembly including a second flexure so that movement of the optical element about the second axis with the second axis movement assembly is decoupled from the movement of the optical element about the first axis; and
wherein the mover assembly includes a linkage that is coupled to the optical element, and a mover that pivots the linkage about a pivot axis; wherein the movement point is in a movement plane defined by the first axis and the second axis, and wherein the pivot axis is not in the movement plane.

8. The optical element assembly of claim 1 wherein for at least one of the plurality of elements the mover assembly includes (i) a first axis movement assembly that moves the optical element about the first axis, the first axis movement assembly including a first mover and a first flexure that flexibly couples the first mover to the optical element so that movement by the first mover causes movement of the optical element about the first axis without movement of the optical element about the second axis; and (ii) a second axis movement assembly that moves the optical element about the second axis, the second axis movement assembly including a second mover and a second flexure that flexibly couples the second mover to the optical element so that movement by the second mover causes movement of the optical element about the second axis without movement of the optical element about the first axis.

9. The optical element assembly of claim 1 wherein for each of the plurality of elements the mover assembly includes (i) a first axis movement assembly that moves the optical element about the first axis, the first axis movement assembly including a first mover and a first flexure that flexibly couples the first mover to the optical element so that movement by the first mover causes movement of the optical element about the first axis without movement of the optical element about the second axis; and (ii) a second axis movement assembly that moves the optical element about the second axis, the second axis movement assembly including a second mover and a second flexure that flexibly coup

Assignees

• Nikon Corp
• Nikon Res Corporation Of America

Inventors

• Margeson Christopher
• Bow Travis

Classifications

• G03F7/70891

  Temperature · 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

• 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

• G02B7/182

  for mirrors · CPC title

• G02B7/181 Primary

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