EXPOSURE APPARATUS, EXPOSURE METHOD, AND DEVICE MANUFACTURING METHOD

• US 20110032495A1
• Filed: 08/06/2010
• Published: 02/10/2011
• Est. Priority Date: 08/07/2009
• Status: Abandoned Application

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: SHIBAZAKI, Yuichi
• Application Number:
  US12/851,857
• Publication Number:
  US 20110032495A1
• Time in Patent Office: Days
• US Class Current: 355/30
• CPC Class Codes: G03F 7/7015 Details of optical elements
• CPC Class Codes: G03F 7/70716 Stages
• CPC Class Codes: G03F 7/70725 control
• CPC Class Codes: G03F 7/70825 Mounting of individual elements, e.g. mounts, holders or supports workpiece or mask holders G03F7/707
• CPC Class Codes: G03F 7/70841 Constructional issues related to vacuum environment, e.g. load-lock chamber
• CPC Class Codes: G03F 7/70866 of mask or workpiece
• CPC Class Codes: G03F 7/70875 Temperature, e.g. temperature control of masks or workpieces via control of stage temperature
• CPC Class Codes: G03F 7/70933 Purge, e.g. exchanging fluid or gas to remove pollutants
• CPC Class Codes: G03F 7/70975 Assembly, maintenance, transport or storage of apparatus

Abstract

A purge cover is equipped whose upper end is connected to an illumination unit and the lower end has a pair of plate sections facing an upper surface of a reticle stage and a reticle via a predetermined clearance. Therefore, gaseous circulation can be substantially blocked via the clearance between reticle stage RST and the plate sections. This allows a space which is almost airtight surrounded by the purge cover, the reticle stage and/or the reticle to be formed on the optical path of the illumination light that reaches the projection optical system from the illumination unit. Further, the space above which is almost airtight serves as a purge space that is purged with CDA and the like.

Claims

1. An exposure apparatus which synchronously moves a mask and an object and transfers a pattern formed on the mask onto the object, the apparatus comprising:

a slider which moves with predetermined strokes in a first direction in which the mask synchronously moves, and holds the mask in a state where an upper surface on both sides in the first direction with the mask in between is substantially flush with the upper surface of the mask;

an illumination system which illuminates the mask by an illumination light; and

an opposing member which has an opposing surface section that faces the upper surface of the slider and the mask via a predetermined clearance gap, placed on the illumination system side with respect to the slider at a position different from an optical path of the illumination light in the first direction, wherein

the upper surface of the mask and the slider are moved proximate to the opposing member at the time of synchronous movement with the object.

2. The exposure apparatus according to claim 1 wherein

at the time of the synchronous movement, a substantially enclosed space is formed by the opposing member and the slider.

3. The exposure apparatus according to claim 1 wherein

the opposing member configures a pert of a cover member whose one end is connected to the illumination system and the other end is configured of the opposing member and covers a part of a space including a part of the optical path of the illumination light.

4. The exposure apparatus according to claim 3 wherein

the cover member turns a space including an optical path of the illumination light from the illumination system to the mask into a substantially airtight state with respect to the outside, along with the slider.

5. The exposure apparatus according to claim 4 wherein

in the space, a particular gas with a high degree of cleanliness is supplied.

6. The exposure apparatus according to claim 4 wherein

the airtight state is a state in which control accuracy of humidity in the space can be maintained at a predetermined level.

7. The exposure apparatus according to claim 4 wherein

the airtight state is a state in which fog generation of an optical member in contact with the space resulting from a presence of moisture can be suppressed to a level so that exposure can be performed without any problems.

8. The exposure apparatus according to claim 3, the apparatus further comprising:

a projection optical system which projects the illumination light outgoing from the mask on the object, wherein

the space including an optical path of the illumination light between the illumination system and the projection optical system is isolated from the outside air by a partition wall which includes the cover member, and

in the space, a particular gas with a high degree of cleanliness is supplied.

9. The exposure apparatus according to claim 8 wherein

the space serves as a purge space which is purged with the particular gas in the inside.

10. The exposure apparatus according to claim 9 wherein

in the particular gas, an amount of at least one of substances responsible for haze and substances accelerating a reaction of haze of the mask is smaller than normal air.

11. The exposure apparatus according to claim 10 wherein

as the particular gas, clean dry air is used.

12. The exposure apparatus according to claim 9 wherein

the cover member includes a cooling member whose surface configures the opposing surface section and cools at least one of the slider and the mask.

13. The exposure apparatus according to claim 12 wherein

the cooling member includes a proximity cooling device which faces at least one of the slider and the mask via a predetermined clearance gap and cools at least one of the mask and the slider.

14. The exposure apparatus according to claim 9, the apparatus further comprising:

a surface plate which movably supports the slider; and

a loop-shaped labyrinth seal which surrounds the optical path of the illumination light between the surface plate and the projection optical system, wherein

a space including an optical path of the illumination light between the mask and the projection optical system serves as another purge space which is purged with the particular gas, and the labyrinth seal also serves as a partition wall which isolates the purged space from the outside air.

15. The exposure apparatus according to claim 14 wherein

as the particular gas, clean dry air is used.

16. The exposure apparatus according to claim 1 wherein

the opposing member includes a cooling member whose surface configures the opposing surface section and cools at least one of the slider and the mask.

17. The exposure apparatus according to claim 16 wherein

the cooling member includes a proximity cooling device which faces at least one of the slider and the mask via a predetermined clearance gap and cools at least one of the mask and the slider.

18. The exposure apparatus according to claim 1 wherein

the slider moves in directions of three degrees of freedom in a two-dimensional plane including the first direction and a second direction which is orthogonal to the first direction.

19. The exposure apparatus according to claim 1 wherein

the opposing member has a pair of the opposing surface sections which are placed apart in the first direction.

20. The exposure apparatus according to claim 19, the apparatus further comprising:

a pair of end cover members which are provided, respectively, on one end and the other end of the slider in the first direction, and face the pair of the opposing surface section via a predetermined clearance gap.

21. The exposure apparatus according to claim 1 wherein

a height difference is present between the upper surface of the slider which is arranged on both sides of the mask in the first direction with the mask in between and the upper surface of the mask, which allows the humidity to be maintained at a predetermined level in a clearance gap formed with the opposing member when the upper surface of the slider and the mask nears the opposing member at the time of synchronous movement.

22. A device manufacturing method, including

transferring a pattern on an object by the exposure apparatus according to claim 1;

and

developing the object on which the pattern is transferred.

23. An exposure apparatus which synchronously moves a mask and an object and transfers a pattern formed on the mask onto the object, the apparatus comprising:

a slider which holds the mask, and moves in a first direction in which the mask is synchronously moved;

an illumination system which illuminates the mask by an illumination light; and

a cooling member which performs temperature control of the mask, and is placed on the illumination system side with respect to the slider at a position different from an optical path of the illumination light in the first direction, wherein

the slider is moved in a state where a surface of the mask is proximal to the cooling member.

24. The exposure apparatus according to claim 23 wherein

the cooling member is placed one each, on one side and the other side in the first direction with the optical path of the illumination light in between.

25. The exposure apparatus according to claim 24, the apparatus further comprising:

a pair of end cover members which are provided, respectively, on one end and the other end of the slider in the first direction, and face a lower surface of each of the cooling members.

26. The exposure apparatus according to claim 24, the apparatus further comprising:

a cover member which has one end connected to the illumination system and the other end covering each of the cooling members.

27. The exposure apparatus according to claim 23, the apparatus further comprising:

a projection optical system which projects the illumination light outgoing from the mask on the object, wherein

a space including an optical path of the illumination light between the illumination system and the projection optical system serves as a purge space purged with purge gas, and the cooling member serves as a part of a partition member which isolates the purge space from the outside air.

28. The exposure apparatus according to claim 27 wherein

as the purge gas, clean dry air is used.

29. The exposure apparatus according to claim 27, the apparatus further comprising:

a surface plate which movably supports the slider; and

a loop-shaped labyrinth seal which surrounds the optical path of the illumination light provided in between the surface plate and the projection optical system, wherein

the labyrinth seal also serves as a partition wall which isolates a space including the optical path of the illumination light between the mask and the projection optical system from the outside air.

30. The exposure apparatus according to claim 29 wherein

an inside of the space isolated from the outside air with the labyrinth seal is purged with purge gas.

31. The exposure apparatus according to claim 30 wherein

as the purge gas, clean dry air is used.

32. The exposure apparatus according to claim 23 wherein

the slider moves in directions of three degrees of freedom in a two-dimensional plane including the first direction and a second direction which is orthogonal to the first direction.

33. The exposure apparatus according to claim 23 wherein

the cooling member includes a proximity cooling device which faces a cooling object via a predetermined clearance gap, and cools the cooling object.

34. The exposure apparatus according to claim 33 wherein

the proximity cooling device cools the cooling object by radiative heat transfer.

35. The exposure apparatus according to claim 23 wherein

at the time of movement, the slider nears the cooling member as much as possible in a direction orthogonal to a two-dimensional plane including the first direction and a second direction orthogonal to the first direction, in a range where a surface of the mask avoids coming into contact with the cooling member.

36. A device manufacturing method, including

transferring a pattern on an abject by the exposure apparatus according to claim 23;

and

developing the object on which the pattern is transferred.

37. An exposure method in which a mask and an object are relatively scanned synchronously in a predetermined direction with respect to an irradiation area by an illumination light, and a pattern formed on the mask is transferred on to the object, the method comprising:

setting a cooling area on at least one side in the predetermined direction of the irradiation area of the illumination light in the vicinity of a movement plane of the mask; and

cooling the mask which passes through the cooling area during relative scanning of the mask and the object with respect to the irradiation area.

38. A device manufacturing method, including

transferring a pattern on an object by the exposure method according to claim 37;

and

developing the object on which the pattern is transferred.

39. An exposure method in which a mask and an object are synchronously moved and a pattern formed on the mask is transferred onto the object, the method comprising:

preparing

a slider which moves with predetermined strokes in a first direction in which the mask synchronously moves, and holds the mask in a state where an upper surface on both sides in the first direction with the mask in between is substantially flush with the upper surface of the mask;

an illumination system which illuminates the mask by an illumination light; and

an opposing member which has an opposing surface section that faces the slider and the upper surface of the mask via a predetermined clearance gap, placed on the illumination system side with respect to the slider at position different from an optical path of the illumination light in the first direction, and

the upper surface of the mask and the slider are moved proximate to the opposing member at the time of the synchronous movement with the object.

40. The exposure method according to claim 39 wherein

at the time of the synchronous movement, a substantially enclosed space is formed by the opposing member and the slider.

41. The exposure method according to claim 39 wherein

the opposing member configures a part of the other end of a cover member whose one end is connected to the illumination system and covers a part of a space including a part of the optical path of the illumination light.

42. The exposure method according to claim 41 wherein

the cover member turns a space including an optical path of the illumination light from the illumination system to the mask into a substantially airtight state with respect to the outside, along with the slider.

43. The exposure method according to claim 42 wherein

in the space, a particular gas with a high degree of cleanliness is supplied.

44. The exposure method according to claim 42 wherein

the airtight state is a state in which control accuracy of humidity in the space can be maintained at a predetermined level.

45. The exposure method according to claim 42 wherein

the airtight state is a state in which fog generation of an optical member in contact with the space resulting from a presence of moisture can be suppressed to a level so that exposure can be performed without any problems.

46. The exposure method according to claim 41 wherein

the space including an optical path of the illumination light between the illumination system and a projection optical system which projects the illumination light outgoing from the mask on the object is isolated from the outside air by a partition wall which includes the cover member, and

in the space, a particular gas with a high degree of cleanliness is supplied.

47. The exposure method according to claim 46 wherein

the space serves as a purge space which is purged with the particular gas in the inside.

48. The exposure method according to claim 47 wherein

in the particular gas, an amount of at least one of substances responsible for haze and substances accelerating a reaction of haze of the mask is smaller than normal air.

49. The exposure method according to claim 48 wherein

as the particular gas, clean dry air is used.

50. The exposure method according to claim 47 wherein

the cover member includes a cooling member whose surface configures the opposing surface section and cools at least one of the slider and the mask.

51. The exposure method according to claim 50 wherein

the cooling member includes a proximity cooling device which faces at least one of the slider and the mask via a predetermined clearance gap and cools at least one of the mask and the slider.

52. The exposure method according to claim 47 wherein

an optical path of the illumination light between a surface plate which movably supports the slider and the projection optical system is surrounded by a loop-shaped labyrinth seal, and

a space including an optical path of the illumination light between the mask and the projection optical system serves as another purge space which is purged with the particular gas, and the labyrinth seal also serves as a partition wall which isolates the another purged space from the outside air.

53. The exposure method according to claim 52 wherein

as the particular gas, clean dry air is used.

54. The exposure method according to claim 39 wherein

the opposing member includes a cooling member whose surface configures the opposing surface section and cools at least one of the slider and the mask.

55. The exposure method according to claim 54 wherein

as the cooling member, a proximity cooling device which faces at least one of the slider and the mask via a predetermined clearance gap and cools at least one of the mask and the slider is used.

56. The exposure method according to claim 39 wherein

the opposing member has a pair of the opposing surface sections which are placed apart in the first direction.

57. The exposure method according to claim 39 wherein

a height difference is present between the upper surface of the slider which is arranged on both sides of the mask in the first direction with the mask in between and the upper surface of the mask, which allows the humidity to be maintained at a predetermined level in a clearance gap formed with the opposing member when the upper surface of the slider and the mask nears the opposing member at the time of synchronous movement.

58. A device manufacturing method, including

transferring a pattern on an object by the exposure method according to claim 39;

and

developing the object on which the pattern is transferred.