Beam transforming element, illumination optical apparatus, exposure apparatus, and exposure method with two optical elements having different thicknesses

• US 20090147235A1
• Filed: 01/27/2009
• Published: 06/11/2009
• Est. Priority Date: 11/20/2003
• Status: Abandoned Application

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: Toyoda, Mitsunori
• Application Number:
  US12/320,480
• Publication Number:
  US 20090147235A1
• Time in Patent Office: Days
• US Class Current: 355/71
• CPC Class Codes: G02B 27/0927 Systems for changing the beam intensity distribution, e.g. Gaussian to top-hat
• CPC Class Codes: G02B 27/0944 Diffractive optical elements, e.g. gratings, holograms gratings per se G02B5/18; holograms used as optical elements per se G02B5/32
• CPC Class Codes: G02B 27/28 for polarising used in stereoscopes G02B30/25
• CPC Class Codes: G02B 27/4233 having a diffractive element [DOE] contributing to a non-imaging application diffusers having a diffractive element G02B5/0252; filters having a diffractive element G02B5/203; systems for controlling the direction of light having diffractive elements G02B26/0808; scanning systems having diffractive elements G02B26/106; beam shaping systems using diffractive optical elements G02B27/0944; beam splitting or combining systems operating by diffraction G02B27/1086
• CPC Class Codes: G02B 27/4261 having a diffractive element with major polarization dependent properties
• CPC Class Codes: G02B 5/3025 Polarisers, i.e. arrangements capable of producing a definite output polarisation state from an unpolarised input state G02B5/3008, G02B5/3016 take precedence
• CPC Class Codes: G03F 7/70091 Illumination settings, i.e. intensity distribution in the pupil plane or angular distribution in the field plane; On-axis or off-axis settings, e.g. annular, dipole or quadrupole settings; Partial coherence control, i.e. sigma or numerical aperture [NA]
• CPC Class Codes: G03F 7/70108 Off-axis setting using a light-guiding element, e.g. diffractive optical elements [DOEs] or light guides
• CPC Class Codes: G03F 7/70158 Diffractive optical elements
• CPC Class Codes: G03F 7/70566 Polarisation control

Abstract

A beam transforming element for forming a predetermined light intensity distribution on a predetermined surface on the basis of an incident beam includes a first basic element made of an optical material with optical activity, for forming a first region distribution of the predetermined light intensity distribution on the basis of the incident beam; and a second basic element made of an optical material with optical activity, for forming a second region distribution of the predetermined light intensity distribution on the basis of the incident beam, wherein the first basic element and the second basic element have their respective thicknesses different from each other along a direction of transmission of light.

Claims

1. An apparatus which illuminates a surface to be illuminated with radiation from a radiation source, the apparatus comprising:

an optical member having a first portion of a first thickness along an optical axis direction of the apparatus and a second portion of a second thickness along the optical axis direction of the apparatus, wherein

the first and second portion thicknesses are different from each other, and the optical member is made of an optical material with optical activity.

2. The apparatus according to claim 1, wherein the optical member includes a first basic element and a second basic element.

3. The apparatus according to claim 2, further comprising:

a diffractive surface arranged in an illumination path of the apparatus which generates a first diffracted radiation and a second diffracted radiation from the radiation from the radiation source, the first and second diffracted radiations reach different regions on an illumination pupil of the apparatus;

the first basic element provides the first diffracted radiation with optical rotation;

the second basic element provides the second diffracted radiation with optical rotation, and the first and second basic element thicknesses are different from each other along a direction of transmission of the radiation.

4. The apparatus according to claim 3, further comprising an optical integrator arranged between the first and second basic elements and the surface to be illuminated.

5. The apparatus according to claim 4, wherein the diffractive surface is arranged between the first and second basic elements and the surface to be illuminated.

6. The apparatus according to claim 3, wherein the diffractive surface is arranged between the first and second basic elements and the surface to be illuminated.

7. The apparatus according to claim 2, wherein the first and second basic elements are arranged in a plane in an illumination path of the apparatus.

8. The apparatus according to claim 2, further comprising:

a diffractive surface which is arranged in an illumination path of the apparatus, and which forms a first region distribution of the predetermined light intensity distribution and a second region distribution of the predetermined light intensity distribution based on the radiation from the radiation source;

the first basic element provides a first rotation angle to an incident linearly polarized radiation and has a first thickness along a direction of transmission of radiation, and a linearly polarized radiation from the first basic element propagates to the first region distribution;

the second basic element provides a second rotation angle to an incident linearly polarized radiation and has a second thickness along a direction of transmission of radiation, the second thickness differs from the first thickness, and a linearly polarized radiation from the second basic element propagates to the second region distribution.

9. The apparatus according to claim 8, further comprising an optical integrator arranged between the first and second basic elements and the surface to be illuminated.

10. The apparatus according to claim 9, wherein the diffractive surface is arranged between the first and second basic elements and the surface to be illuminated.

11. The apparatus according to claim 8, wherein the diffractive surface is arranged between the first and second basic elements and the surface to be illuminated.

12. The apparatus according to claim 2, further comprising a diffractive surface arranged in an illumination path of the apparatus which generates a first diffracted radiation and a second diffracted radiation based on the radiation from the radiation source, the first and second diffracted radiations reach different regions on an illumination pupil of the apparatus.

13. The apparatus according to claim 12, wherein the diffractive surface forms an illumination pupil distribution which is formed on or near an illumination pupil of the apparatus.

14. The apparatus according to claim 2, wherein the first basic element and the second basic element are integrally formed.

15. The apparatus according to claim 1, further comprising an optical integrator arranged between the optical member and the surface to be illuminated.

16. The apparatus according to claim 1, further comprising:

a first optical unit including a first optical axis;

a second optical unit including a second optical axis which crosses the first optical axis, the first optical unit arranged in an illumination path between the radiation source and the second optical unit;

a third optical unit including a third optical axis which crosses the second optical axis, and the third optical unit is arranged in an illumination path between the second optical unit and the surface to be illuminated, wherein

the second optical unit includes the optical member.

17. The apparatus according to claim 16, wherein the optical member includes a first basic element and a second basic element.

18. The apparatus according to claim 17, further comprising:

a diffractive surface arranged in an illumination path of the apparatus which generates a first diffracted radiation and a second diffracted radiation based on the radiation from the radiation source, the first and second diffracted radiations reach different regions on an illumination pupil of the apparatus;

the first basic element provides the first diffracted radiation with optical rotation; and

the second basic element provides the second diffracted radiation with optical rotation, wherein

the first and second basic elements have thicknesses that are different from each other along a direction of transmission of the radiation.

19. The apparatus according to claim 16, wherein the second optical unit includes an optical integrator.

20. The apparatus according to claim 19, wherein the second optical unit includes a mask blind.

21. The apparatus according to claim 16, wherein the first basic element and the second basic element are integrally formed.

22. The apparatus according to claim 16, wherein the third optical unit includes a folding mirror.

23. The apparatus according to claim 16, wherein the second optical unit includes a polarization state converter.

24. The apparatus according to claim 23, wherein the optical member is arranged in an illumination path between the polarization converter and the third optical unit.

25. The apparatus according to claim 1, further comprising a polarization state converter arranged in an illumination path between the radiation source and the optical member.

26. The apparatus according to claim 1, wherein a polarization state of the beam from the optical member is set based on an influence of a second optical member in an illumination path between the light source and a substrate arranged surface.

27. The apparatus according to claim 26, wherein the second optical member includes a reflective member.

28. An exposure apparatus comprising the apparatus as defined in claim 1, which illuminates a predetermined pattern, and which projects the predetermined pattern onto a photosensitive substrate.

29. The exposure apparatus according to claim 28, wherein an illumination pupil distribution on or near an illumination pupil of the apparatus is a distribution in at least a part of a predetermined annular region centered around an optical axis of the apparatus.

30. The exposure apparatus according to claim 29, wherein a polarization state of the beam at the illumination pupil is set based on an influence of a second optical member disposed in an optical path between the light source and the photosensitive substrate.

31. The exposure apparatus according to claim 30, wherein the second optical member includes a reflective surface.

32. The exposure apparatus according to claim 31, wherein the polarization state of the beam at the illumination pupil is set so that light illuminating the photosensitive substrate is in a polarization state in which a principal component is s-polarized light.

33. An exposure apparatus comprising the apparatus as defined in claim 16, which illuminates a predetermined pattern, and that projects the predetermined pattern onto a photosensitive substrate.

34. The exposure apparatus according to claim 33, wherein an illumination pupil distribution on or near an illumination pupil of the apparatus is a distribution in at least a part of a predetermined annular region centered around an optical axis of the apparatus.

35. The exposure apparatus according to claim 33, wherein a polarization state of the beam at the illumination pupil is set based on an influence of a second optical member in an optical path between the light source and the photosensitive substrate.

36. The exposure apparatus according to claim 35, wherein the second optical member includes a reflective surface.

37. The exposure apparatus according to claim 36, wherein the polarization state of the beam at the illumination pupil is set so that light illuminating the photosensitive substrate is in a polarization state in which a principal component is s-polarized light.

38. An exposure apparatus comprising the apparatus as defined in claim 25, which illuminates a predetermined pattern, and that projects the predetermined pattern onto a photosensitive substrate.

39. The exposure apparatus according to claim 38, wherein an illumination pupil distribution on or near an illumination pupil of the apparatus is a distribution in at least a part of a predetermined annular region centered around an optical axis of the apparatus.

40. The exposure apparatus according to claim 39, wherein a polarization state of the beam at the illumination pupil is set based on an influence of a second optical member in an optical path between the light source and the photosensitive substrate.

41. The exposure apparatus according to claim 40, wherein the second optical member including a reflective surface.

42. The exposure apparatus according to claim 41, wherein the polarization state of the beam at the illumination pupil is set so that light illuminating the photosensitive substrate is in a polarization state in which a principal component is s-polarized light.

43. An exposure method comprising:

illuminating a predetermined pattern using the exposure apparatus as defined in claim 28; and

projecting an image of the predetermined pattern onto a photosensitive substrate.

44. A device manufacturing method comprising:

illuminating a predetermined pattern using the exposure apparatus as defined in claim 28;

projecting an image of the predetermined pattern onto a photosensitive substrate; and

developing the photosensitive substrate.

45. An exposure method comprising:

illuminating a predetermined pattern using the exposure apparatus as defined in claim 33; and

projecting an image of the predetermined pattern onto a photosensitive substrate.

46. A device manufacturing method comprising:

illuminating a predetermined pattern using the exposure apparatus as defined in claim 33;

projecting an image of the predetermined pattern onto a photosensitive substrate; and

developing the photosensitive substrate.

47. An exposure method comprising:

illuminating a predetermined pattern using the exposure apparatus as defined in claim 38; and

projecting an image of the predetermined pattern onto a photosensitive substrate.

48. A device manufacturing method comprising:

illuminating a predetermined pattern using the exposure apparatus as defined in claim 38;

projecting an image of the predetermined pattern onto a photosensitive substrate; and

developing the photosensitive substrate.

68. The apparatus according to claim 2, wherein the first basic element and the second basic element are made of same optical material.

69. The apparatus according to claim 17, wherein the first basic element and the second basic element are made of same optical material.

49. An exposure method comprising:

supplying radiation;

passing the radiation through an optical member made of an optical material with optical activity, the optical member including a first thickness along a traveling direction of an incident radiation and a second thickness along a traveling direction of an incident radiation, the first and second thicknesses are different from each other;

illuminating a pattern with radiation that has passed through the optical member; and

projecting an image of the pattern using the radiation with which the pattern was illuminated.

50. The method according to claim 49, wherein the passing the radiation through the optical member includes passing the radiation through a first basic element and a second basic element.

51. The method according to claim 50, further comprising:

generating a first diffracted radiation and a second diffracted radiation, the first and second diffracted radiations reach different regions on an illumination pupil;

optically rotating the first diffracted radiation with the first basic element; and

optically rotating the second diffracted radiation with the second basic element, wherein

the first and second basic elements have thicknesses different from each other along a direction of transmission of the radiation.

52. The method according to claim 51, further comprising passing the radiations from the first and second basic elements through an optical integrator.

53. The method according to claim 52, wherein the first and second diffracted radiations are generated by radiations from the first and second basic elements.

54. The method according to claim 51, wherein the first and second diffracted radiations are generated by radiations from the first and second basic elements.

55. The method according to claim 50, wherein the first and second basic elements are in an illumination path of the radiation.

56. The method according to claim 50, wherein the first basic element and the second basic element are integrally formed.

57. The method according to claim 49, wherein a polarization state of the beam at an illumination pupil is set based on a second optical member in an optical path upstream of the photosensitive substrate.

58. The method according to claim 57, wherein the second optical member includes a reflective surface.

59. A device manufacturing method comprising:

projecting an image of a pattern onto a photosensitive substrate using the exposure method according to claim 49; and

developing the photosensitive substrate.

70. The method according to claim 50, wherein the first basic element and the second basic element are made of same optical material.

60. An exposure method comprising:

supplying radiation;

folding the supplied radiation;

passing the folded radiation through an optical member made of an optical material with optical activity, the optical member including a first portion having a first thickness along a traveling direction of an incident radiation and a second portion having a second thickness along a traveling direction of an incident radiation, the first and second portions having thicknesses that are different from each other;

folding the radiation that has passed through the optical member;

illuminating a pattern by use of the folded radiation that has passed through the optical member; and

projecting an image of the pattern using the radiation with which the pattern was illuminated.

61. The method according to claim 60, wherein a polarization state of the beam at an illumination pupil is set based on an influence of a second optical member disposed in an optical path upstream of the photosensitive substrate.

62. The method according to claim 61, wherein the second optical member includes a reflective surface.

63. A device manufacturing method comprising:

projecting an image of a pattern onto a photosensitive substrate using the exposure method according to claim 60; and

developing the photosensitive substrate.

71. The method according to claim 60, wherein the optical member includes a first basic element including the first thickness and a second basic element including the second thickness.

72. The method according to claim 71, wherein the first basic element and the second basic element are made of same optical material.

64. An exposure method comprising:

supplying radiation;

passing the supplied radiation through a polarization state converter;

passing the radiation from the polarization state converter through an optical member made of an optical material with optical activity, the optical member including a first thickness along a traveling direction of an incident radiation and a second thickness along a traveling direction of an incident radiation, and the first and second thicknesses being different from each other;

illuminating a pattern with the radiation that has passed through the optical member; and

projecting an image of the pattern image using the radiation with which the pattern was illuminated.

65. The method according to claim 64, wherein a polarization state of the beam at an illumination pupil is set based on an influence of a second optical member disposed in an optical path upstream of the photosensitive substrate.

66. The method according to claim 65, wherein the second optical member includes a reflective surface.

67. A device manufacturing method comprising:

projecting an image of a pattern onto a photosensitive substrate using the exposure method according to claim 64; and

developing the photosensitive substrate.

73. The method according to claim 64, wherein the optical member includes a first basic element including the first thickness and a second basic element including the second thickness.

74. The method according to claim 73, wherein the first basic element and the second basic element are made of same optical material.