SPATIAL LIGHT MODULATING UNIT, ILLUMINATION OPTICAL SYSTEM, EXPOSURE APPARATUS, AND DEVICE MANUFACTURING METHOD

• US 20100253927A1
• Filed: 06/17/2010
• Published: 10/07/2010
• Est. Priority Date: 12/17/2007
• Status: Abandoned Application

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: TANITSU, Osamu
• Application Number:
  US12/817,299
• Publication Number:
  US 20100253927A1
• Time in Patent Office: Days
• US Class Current: 355/67
• CPC Class Codes: G02B 26/0808 by means of one or more diffracting elements
• CPC Class Codes: G02B 26/0833 the reflecting element being a micromechanical device, e.g. a MEMS mirror, DMD G02B26/0825 takes precedence; micromechanical devices in general B81B
• CPC Class Codes: G02B 26/0883 the refracting element being a prism
• CPC Class Codes: G02B 27/42 Diffraction optics , i.e. systems including a diffractive element being designed for providing a diffractive effectG02B27/60 takes precedence
• CPC Class Codes: G03F 7/70116 Off-axis setting using a programmable means, e.g. liquid crystal display [LCD], digital micromirror device [DMD] or pupil facets

Abstract

There is disclosed a spatial light modulating unit comprising:

a spatial light modulator having a plurality of optical elements arrayed two-dimensionally and controlled individually; and an angle varying unit which varies a relative angle between a diffracted light generating region to generate diffracted light around each of the plurality of optical elements, and incident light to the diffracted light generating region.

Claims

1. A spatial light modulating unit comprising:

a spatial light modulator having a plurality of optical elements arrayed two-dimensionally and controlled individually; and

angle varying unit which varies a relative angle between a diffracted light generating region to generate diffracted light around each of the plurality of optical elements, and incident light to the diffracted light generating region.

2. The spatial light modulating unit according to claim 1, wherein the angle varying unit has first varying unit which varies a posture of the diffracted light generating region.

3. The spatial light modulating unit according to claim 1 wherein the angle varying unit has second varying unit which varies a direction of the incident light to the diffracted light generating region.

4. The spatial light modulating unit according to of claims 1, wherein the spatial light modulator has a plurality of mirror elements arrayed two-dimensionally, and a drive unit which individually controls and drives postures of the plurality of mirror elements.

5. The spatial light modulating unit according to claim 4, wherein the drive unit continuously varies orientations of the plurality of mirror elements.

6. The spatial light modulating unit according to claim 4, further comprising a control unit which controls the drive unit in order to vary the postures of the plurality of mirror elements according to variation in the relative angle by the angle varying unit.

7. The spatial light modulating unit according to claim 4, further comprising an optical surface provided on the light entrance side of the plurality of mirror elements.

8. The spatial light modulating unit according to claim 7, wherein the second varying means varies a posture of the optical surface.

9. The spatial light modulating unit according to claim 7, wherein the second varying unit varies a direction of light incident to the optical surface.

10. The spatial light modulating unit according to claim 7, wherein the optical surface comprises a reflecting surface or a refracting surface.

11. The spatial light modulating unit according to claim 7, further comprising a prism member having the optical surface.

12. The spatial light modulating unit according to claim 4, further comprising a prism member having an optical surface opposed to a plane where the plurality of mirror elements are arrayed.

13. The spatial light modulating unit according to claim 12, wherein the second varying unit varies a posture of the prism member.

14. The spatial light modulating unit according to claim 12, wherein the second varying unit varies a direction of light incident to the prism member.

15. An illumination optical system which illuminates an illumination target surface on the basis of light from a light source, the illumination optical system comprising:

the spatial light modulating unit as set forth in claim 1; and

a distribution forming optical system which forms a predetermined light intensity distribution on an illumination pupil of the illumination optical system, based on a flux of light having traveled via the spatial light modulator.

17. The illumination optical system according to claim 15, wherein the distribution forming optical system has an optical integrator, and a condensing optical system arranged in an optical path between the optical integrator and the spatial light modulating unit.

18. The illumination optical system according to claim 15, wherein the plurality of optical elements are controlled so as to keep the predetermined light intensity distribution still on the illumination pupil with variation in the relative angle by the angle varying means.

19. The illumination optical system according to claim 15, which is used in combination with a projection optical system for forming a plane optically conjugate with the illumination target surface, wherein the illumination pupil is a position optically conjugate with an aperture stop of the projection optical system.

20. An exposure apparatus comprising the illumination optical system as set forth in claim 15 for illuminating a predetermined pattern, wherein the predetermined pattern is transferred onto a photosensitive substrate to effect exposure thereof.

21. A device manufacturing method comprising:

transferring the predetermined pattern onto the photosensitive substrate to effect exposure thereof, using the exposure apparatus as set forth in claim 20;

developing the photosensitive substrate on which the predetermined pattern is transferred, to form a mask layer of a shape corresponding to the predetermined pattern, on a surface of the photosensitive substrate; and

processing the surface of the photosensitive substrate through the mask layer.

16. An illumination optical system which illuminates an illumination target surface on the basis of light from a light source, said illumination optical system comprising:

a spatial light modulator having a plurality of optical elements arrayed two-dimensionally and controlled individually, and a diffracted light generating region which generates diffracted light around each of the plurality of optical elements; and

a light-guiding optical system which guides the light from the light source to the spatial light modulator,

wherein a posture of at least one of the spatial light modulator and at least a part of the light-guiding optical system is variable in order to vary a relative angle between the diffracted light generating region and incident light to the diffracted light generating region.