Projection Optical System, Exposure Equipment and Exposure Method

• US 20080123074A1
• Filed: 10/26/2005
• Published: 05/29/2008
• Est. Priority Date: 11/10/2004
• Status: Abandoned Application

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: Fujishima, Youhei
• Application Number:
  US11/666,725
• Publication Number:
  US 20080123074A1
• Time in Patent Office: Days
• US Class Current: 355/71
• CPC Class Codes: G02B 13/143 for use with ultraviolet radiation
• CPC Class Codes: G02B 13/22 Telecentric objectives or lens systems
• CPC Class Codes: G02B 13/24 for reproducing or copying at short object distances
• CPC Class Codes: G03F 7/70241 Optical aspects of refractive lens systems, i.e. comprising only refractive elements
• CPC Class Codes: G03F 7/70341 Details of immersion lithography aspects, e.g. exposure media or control of immersion liquid supply chemical composition of immersion liquids G03F7/2041
• CPC Class Codes: G03F 7/706 Aberration measurement

Abstract

A projection optical system is a system with good imaging performance based on well-balanced compensation for aberration associated with image height and aberration associated with numerical aperture, while ensuring a large effective image-side numerical aperture in the presence of a liquid in the optical path between the projection optical system and an image plane. The projection optical system forms an image of a first plane on a second plane. An optical path between an optical member located nearest to the second plane out of optical members with a refractive power in the projection optical system, and the second plane is fillable with a predetermined liquid. The projection optical system satisfies the condition of 0.02<NA×WD/FA<0.08, where NA is a numerical aperture on the second plane side of the projection optical system, WD a distance along the optical axis between an optical member located nearest to the first plane in the projection optical system, and the first plane, and FA a maximum of effective diameters of all optical surfaces in the projection optical system.

Claims

1-20. -20. (canceled)

21. A projection optical system which forms an image of a first plane on a second plane, comprising:

a first lens unit disposed in an optical path between the first plane and the second plane;

a second lens unit with a positive refractive power disposed subsequently to an image side of the first lens unit;

a third lens unit with a negative refractive power disposed subsequently to an image side of the second lens unit;

a fourth lens unit with a positive refractive power disposed subsequently to an image side of the third lens unit; and

a fifth lens unit with a positive refractive power disposed subsequently to an image side of the fourth lens unit;

wherein the first lens unit comprises a first lens of a biconcave shape disposed nearest to the first plane;

a first meniscus lens which is disposed subsequently to the first lens and a concave surface of which is directed toward an object side;

a second meniscus lens which is disposed subsequently to the first meniscus lens and a concave surface of which is directed toward the object side;

a third meniscus lens which is disposed subsequently to the second meniscus lens and a concave surface of which is directed toward the object side; and

a fourth meniscus lens which is disposed subsequently to the third meniscus lens and a concave surface of which is directed toward the object side;

wherein the third lens unit comprises a front negative lens which is disposed nearest to the object side in the third lens unit and a concave surface of which is directed toward the image side; and

a rear negative lens which is disposed nearest to the image side in the third lens unit and a concave surface of which is directed toward the object side;

wherein an aperture stop is disposed between the fourth lens unit and the fifth lens unit;

wherein the fifth lens unit comprises an optical member located nearest to the second plane among optical members with a refractive power in the projection optical system; and

wherein an optical path between the optical member located nearest to the second plane in the fifth lens unit, and the second plane is fillable with a predetermined liquid.

22. The projection optical system according to claim 21, wherein the second lens unit comprises a second lens disposed adjacent to the fourth meniscus lens in the first lens unit and so shaped that a convex surface thereof is directed toward the fourth meniscus lens.

23. The projection optical system according to claim 22, wherein the third lens unit comprises a third lens which is disposed in an optical path between the front negative lens and the rear negative lens and a convex surface of which is directed toward the first plane.

24. The projection optical system according to claim 23, wherein every optical member with a refractive power in the fifth lens unit is a positive lens.

25. The projection optical system according to claim 24, which satisfies the following condition:

0.4<

F1/L<

0.8,

where F1 is a focal length of the first lens unit and L an overall length of the projection optical system.

26. The projection optical system according to claim 25, which satisfies the following condition:

−

0.4<

F5/F3<

−

0.3,

where F3 is a focal length of the third lens unit.

27. The projection optical system according to claim 21, which satisfies the following condition:

0.02<

NA×

WD/FA<

0.08,

where NA is a numerical aperture on the second plane side of the projection optical system, WD a distance along the optical axis between the optical member located nearest to the first plane in the projection optical system, and the first plane, and FA a maximum of effective diameters of all optical surfaces in the projection optical system.

28. The projection optical system according to claim 27, which satisfies the following condition:

0.2<

NA×

FS/FA<

0.6,

where NA is a numerical aperture on the second plane side of the projection optical system, FA a maximum of effective diameters of all optical surfaces in the projection optical system, and FS a smaller effective diameter out of an effective diameter of an optical surface on the first plane side of the first lens and an effective diameter of an optical surface on the second plane side of the first lens.

29. The projection optical system according to claim 28, wherein at least one optical surface out of an optical surface on the first plane side of the first lens and an optical surface on the second plane side of the first lens includes an aspherical shape.

30. The projection optical system according to claim 21 wherein the third lens unit comprises a third lens which is disposed in an optical path between the front negative lens and the rear negative lens and a convex surface of which is directed toward the first plane.

31. The projection optical system according to claim 21, wherein every optical member with a refractive power in the fifth lens unit is a positive lens.

32. The projection optical system according to claim 21, which satisfies the following condition:

0.4<

F1/L<

0.8,

where F1 is a focal length of the first lens unit and L an overall length of the projection optical system.

33. The projection optical system according to claim 32, which satisfies the following condition:

−

0.4<

F5/F3<

−

0.3,

where F3 is a focal length of the third lens unit.

34. The projection optical system according to claim 21, which satisfies the following condition:

0.02<

NA×

WD/FA<

0.08,

where NA is a numerical aperture on the second plane side of the projection optical system, WD a distance along the optical axis between the optical member located nearest to the first plane in the projection optical system, and the first plane, and FA a maximum of effective diameters of all optical surfaces in the projection optical system.

35. The projection optical system according to claim 21, which satisfies the following condition:

0.2<

NA×

FS/FA<

0.6,

where NA is a numerical aperture on the second plane side of the projection optical system, FA a maximum of effective diameters of all optical surfaces in the projection optical system, and FS a smaller effective diameter out of an effective diameter of an optical surface on the first plane side of the first lens and an effective diameter of an optical surface on the second plane side of the first lens.

36. The projection optical system according to claim 21, wherein at least one optical surface out of an optical surface on the first plane side of the first lens and an optical surface on the second plane side of the first lens has an aspherical shape.

37. An exposure apparatus comprising the projection optical system as defined in claim 21, which projects an image of a pattern set on the first plane, onto a photosensitive substrate set on the second plane.

38. The exposure apparatus according to claim 37, which comprises an illumination system which illuminates the pattern of a mask, a mask stage which holds and moves the mask, a mask stage platen which movably mounts the mask stage through a guide surface, and an interferometer which projects a measurement beam toward the mask stage in order to measure a position of the mask stage,

wherein the measurement beam is projected to a position on the projection optical system side with respect to the guide surface.

39. An exposure method comprising:

setting a photosensitive substrate on the second plane; and

projecting an image of a pattern set on the first plane, onto the photosensitive substrate set on the second plane, through the projection optical system as defined in claim 21, to effect exposure thereof.

40. The exposure method according to claim 39, comprising:

illuminating the mask on a mask stage movably holding the mask; and

measuring a position of the mask with a measurement beam from an interferometer;

wherein the projecting comprises performing the projection exposure while moving the mask stage along a guide surface of a mask stage platen, and moving the photosensitive substrate, and

wherein the measuring comprises projecting the measurement beam from the interferometer to a position on the projection optical system side with respect to the guide surface of the mask stage platen.

41. A device manufacturing method comprising:

setting a photosensitive substrate on the second plane;

projecting an image of a pattern of a mask set on the first plane, onto the photosensitive substrate set on the second plane, through the projection optical system as defined in claim 21, to effect exposure thereof; and

developing the photosensitive substrate.

42. The device manufacturing method according to claim 41, comprising:

illuminating the mask on a mask stage movably holding the mask; and

measuring a position of the mask with a measurement beam from an interferometer;

wherein the projecting comprises performing the projection exposure while moving the mask stage along a guide surface of a mask stage platen, and moving the photosensitive substrate, and

wherein the measuring comprises projecting the measurement beam from the interferometer to a position on the projection optical system side with respect to the guide surface of the mask stage platen.

43. A projection optical system which forms an image of a first plane on a second plane,

wherein an optical path between an optical member located nearest to the second plane among optical members with a refractive power in the projection optical system, and the second plane is fillable with a predetermined liquid, the projection optical system satisfying the following condition:

0.02<

NA×

WD/FA<

0.08,

where NA is a numerical aperture on the second plane side of the projection optical system, WD a distance along the optical axis between an optical member located nearest to the first plane in the projection optical system, and the first plane, and FA a maximum of effective diameters of all optical surfaces in the projection optical system.

44. The projection optical system according to claim 43, which satisfies the following condition:

0.2<

NA×

FS/FA<

0.6,

where FS is a smaller effective diameter out of an effective diameter of an optical surface on the first plane side of a negative lens nearest to the first plane in the projection optical system and an effective diameter of an optical surface on the second plane side of the negative lens.

45. The projection optical system according to claim 44, wherein at least one optical surface out of the optical surface on the first plane side of the negative lens and the optical surface of the second plane side of the negative lens includes an aspherical shape.

46. The projection optical system according to claim 44, wherein no positive lens is disposed in an optical path between the first plane and the negative lens.

47. An exposure apparatus comprising the projection optical system as defined in claim 43, which projects an image of a pattern set on the first plane, onto a photosensitive substrate set on the second plane.

48. The exposure apparatus according to claim 47, which comprises an illumination system which illuminates the pattern of a mask, a mask stage which holds and moves the mask, a mask stage platen which movably mounts the mask stage through a guide surface, and an interferometer which projects a measurement beam toward the mask stage in order to measure a position of the mask stage,

wherein the measurement beam is projected to a position on the projection optical system side with respect to the guide surface.

49. An exposure method comprising:

setting a photosensitive substrate on the second plane; and

projecting an image of a pattern set on the first plane, onto the photosensitive substrate set on the second plane, through the projection optical system as defined in claim 43, to effect exposure thereof.

50. The exposure method according to claim 49, comprising:

illuminating the mask on a mask stage movably holding the mask; and

measuring a position of the mask with a measurement beam from an interferometer;

wherein the projecting comprises performing the projection exposure while moving the mask stage along a guide surface of a mask stage platen, and moving the photosensitive substrate, and

wherein the measuring comprises projecting the measurement beam from the interferometer to a position on the projection optical system side with respect to the guide surface of the mask stage platen.

51. A device manufacturing method comprising:

setting a photosensitive substrate on the second plane;

projecting an image of a pattern of a mask set on the first plane, onto the photosensitive substrate set on the second plane, through the projection optical system as defined in claim 43, to effect exposure thereof; and

developing the photosensitive substrate.

52. The device manufacturing method according to claim 51, comprising:

illuminating the mask on a mask stage movably holding the mask; and

measuring a position of the mask with a measurement beam from an interferometer;

wherein the projecting comprises performing the projection exposure while moving the mask stage along a guide surface of a mask stage platen, and moving the photosensitive substrate, and

wherein the measuring comprises projecting the measurement beam from the interferometer to a position on the projection optical system side with respect to the guide surface of the mask stage platen.

53. A projection optical system which forms an image of a first plane on a second plane,

wherein an optical path between an optical member located nearest to the second plane among optical members with a refractive power in the projection optical system, and the second plane is fillable with a predetermined liquid,

the projection optical system satisfying the following condition:

0.2<

NA×

FS/FA<

0.6,

where NA is a numerical aperture on the second plane side of the projection optical system, FA a maximum of effective diameters of all optical surfaces in the projection optical system, and FS a smaller effective diameter out of an effective diameter of an optical surface on the first plane side of a negative lens nearest to the first plane in the projection optical system and an effective diameter of an optical surface on the second plane side of the negative lens.

54. The projection optical system according to claim 53, wherein at least one optical surface out of the optical surface on the first plane side of the negative lens and the optical surface of the second plane side of the negative lens has an aspherical shape.

55. The projection optical system according to claim 53, wherein no positive lens is disposed in an optical path between the first plane and the negative lens.

56. An exposure apparatus comprising the projection optical system as defined in any one of claim 53, which projects an image of a pattern set on the first plane, onto a photosensitive substrate set on the second plane.

57. The exposure apparatus according to claim 56, which comprises an illumination system which illuminates the pattern of a mask, a mask stage which holds and moves the mask, a mask stage platen which movably mounts the mask stage through a guide surface, and an interferometer which projects a measurement beam toward the mask stage in order to measure a position of the mask stage,

wherein the measurement beam is projected to a position on the projection optical system side with respect to the guide surface.

58. An exposure method comprising:

setting a photosensitive substrate on the second plane; and

projecting an image of a pattern set on the first plane, onto the photosensitive substrate set on the second plane, through the projection optical system as defined in claim 53, to effect exposure thereof.

59. The exposure method according to claim 58, comprising:

illuminating the pattern on a mask on a mask stage movably holding the mask; and

measuring a position of the mask with a measurement beam from an interferometer;

wherein the projecting comprises performing the projection exposure while moving the mask stage along a guide surface of a mask stage platen, and moving the photosensitive substrate, and

wherein the measuring comprises projecting the measurement beam from the interferometer to a position on the projection optical system side with respect to the guide surface of the mask stage platen.

60. A device manufacturing method comprising:

setting a photosensitive substrate on the second plane;

projecting an image of a pattern set on the first plane, onto the photosensitive substrate set on the second plane, through the projection optical system as defined in claim 53, to effect exposure thereof; and

a development step of developing the photosensitive substrate.

61. The device manufacturing method according to claim 60, comprising:

illuminating the pattern on a mask on a mask stage movably holding the mask; and

measuring a position of the mask with a measurement beam from an interferometer;

wherein the projecting comprises performing the projection exposure while moving the mask stage along a guide surface of a mask stage platen, and moving the photosensitive substrate, and

wherein the measuring comprises projecting the measurement beam from the interferometer to a position on the projection optical system side with respect to the guide surface of the mask stage platen.