Exposure apparatus, exposure method, and method for producing device

• US 8,130,361 B2
• Filed: 04/07/2006
• Issued: 03/06/2012
• Est. Priority Date: 10/09/2003
• Status: Expired due to Fees

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: Nagayama, Tadashi, Shiraishi, Kenichi, Yasuda, Masahiko, Masada, Takahiro, Kanaya, Yuho
• Primary Examiner(s): Kim, Peter B
• Application Number:
  US11/399,537
• Publication Number:
  US 20060187432A1
• Time in Patent Office: 2,160 Days
• Field of Search: 355/53, 355/72, 355/77, 355/67, 355/30, 355/75, 378/34, 378/35, 430/322, 250/492.2
• US Class Current: 355/53
• CPC Class Codes: G03F 7/70141 Illumination system adjustment, e.g. adjustments during exposure or alignment during assembly of illumination system
• 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 7/70716 Stages
• CPC Class Codes: G03F 9/7088 Alignment mark detection, e.g. TTR, TTL, off-axis detection, array detector, video detection

Abstract

An exposure apparatus includes a substrate stage movable while holding a substrate, a substrate alignment system which detects an alignment mark (1) on the substrate held by the substrate stage and detects a reference mark (PFM) provided on the substrate stage, and a mask alignment system which detects, via a projection optical system, a reference mark (MFM) provided on the substrate stage. The reference mark (PFM) on the substrate stage is detected without a liquid by using the substrate alignment system, and the reference mark (MFM) on the substrate stage is detected using the mask alignment system via the projection optical system and the liquid. Then, a positional relationship between a detection reference position of the substrate alignment system and a projection position of an image of a pattern is obtained, thereby accurately performing alignment processing in the liquid immersion exposure.

Claims

1. An exposure apparatus which exposes a substrate by projecting an image of a pattern onto the substrate through a liquid, the exposure apparatus comprising:

a projection optical system which projects the image of the pattern onto the substrate;

a substrate stage which is movable and which holds the substrate;

a first detecting system which detects an alignment mark on the substrate held by the substrate stage and which detects a reference provided on the substrate stage; and

a second detecting system which detects the reference provided on the substrate stage via the projection optical system, wherein;

the reference includes a first reference and a second reference, and the first reference is detected not through the liquid by using the first detecting system and the second reference is detected via the projection optical system and the liquid by using the second detecting system to determine a positional relationship between a detection reference position of the first detecting system and a projection position of the image of the pattern.

2. The exposure apparatus according to claim 1, wherein the alignment mark is formed on the substrate as a plurality of alignment marks, and position information about the plurality of alignment marks is detected by using the first detecting system;

and the substrate is positioned on the basis of the position information detected by using the first detecting system and the positional relationship between the detection reference position and the projection position to expose the substrate.

3. The exposure apparatus according to claim 1, wherein position information of the alignment mark is detected by the first detecting system not through the liquid.

4. The exposure apparatus according to claim 1, wherein the substrate stage includes a substrate holder which holds the substrate, and the second reference is detected by the second detecting system in a state in which the substrate or a dummy substrate is held by the substrate holder.

5. The exposure apparatus according to claim 1, wherein the first reference and the second reference are arranged separately in a predetermined positional relationship.

6. The exposure apparatus according to claim 5, wherein detection of the first reference by the first detecting system is performed simultaneously with detection of the second reference by the second detecting system.

7. The exposure apparatus according to claim 1, further comprising a nozzle member which has at least any one of a supply port to supply the liquid and a recovery port to recover the liquid, and a control unit which determines a movement locus of the substrate stage to arrange the alignment mark in a detection area of the first detecting system in accordance with a positional relationship between the first detecting system and the nozzle member.

8. The exposure apparatus according to claim 7, wherein the control unit determines the movement locus of the substrate stage so that the alignment mark does not pass across a position under the nozzle member before the alignment mark is arranged in the detection area of the first detecting system.

9. A method for producing a device, comprising using the exposure apparatus as defined in claim 1.

11. The exposure apparatus according to claim 1, wherein the second detecting system detects the second reference provided on the substrate stage via the projection optical system and a mask having the pattern.

12. The exposure apparatus according to claim 1, wherein the second reference is formed on a reference member which is arranged on the substrate stage, and a space between an end surface of the projection optical system and an upper surface of the reference member is filled with the liquid when the second reference formed on the reference member is detected by the second detecting system.

13. The exposure apparatus according to claim 12, wherein at least a part of the upper surface of the reference member is liquid-repellent.

14. The exposure apparatus according to claim 12, wherein the upper surface of the reference member is free from any difference in height.

10. An exposure apparatus which exposes a substrate by projecting an image of a pattern onto the substrate through a liquid, the exposure apparatus comprising:

a projection optical system which projects the image of the pattern onto the substrate through the liquid covering only a portion of a surface of the substrate;

a substrate stage which has a substrate holder to hold the substrate and which is movable;

a first detecting system which detects an alignment mark on the substrate held by the substrate holder; and

a second detecting system which detects a reference provided on the substrate stage through the liquid, the reference being arranged away from the substrate holder,

wherein;

a dummy substrate is arranged on the substrate holder when the reference provided on the substrate stage is detected through the liquid by using the second detecting system.

15. The exposure apparatus according to claim 10, wherein the second detecting system detects the reference provided on the substrate stage via the projection optical system and a mask having the pattern.

16. The exposure apparatus according to claim 10, wherein the reference is formed on a reference member which is arranged on the substrate stage, and a space between an end surface of the projection optical system and an upper surface of the reference member is filled with the liquid when the reference formed on the reference member is detected by the second detecting system.

17. The exposure apparatus according to claim 16, wherein the upper surface of the reference member is free from any difference in height.

18. The exposure apparatus according to claim 16, wherein at least a part of the upper surface of the reference member is liquid-repellent.

19. A method for producing a device, the method comprising:

exposing a substrate by projecting an image of a pattern onto the substrate through the projection optical system of the exposure apparatus as defined in claim 10; and

processing the exposed substrate to produce the device.

20. An exposure apparatus which exposes a substrate by projecting an image of a pattern onto the substrate through a liquid, the exposure apparatus comprising:

a projection optical system which projects the image of the pattern onto the substrate;

a reference member which has an upper surface having no difference in level, at least a part of the upper surface being liquid-repellent; and

a detecting system which detects a reference formed on the reference member in a state in which a space between an end surface of the projection optical system and the upper surface of the reference member is filled with the liquid.

21. The exposure apparatus according to claim 20, further comprising a stage which is movable on an image plane side of the projection optical system, wherein the reference member is arranged on the stage.

22. The exposure apparatus according to claim 21, wherein the stage holds the substrate.

23. A method for producing a device, the method comprising:

exposing a substrate by projecting an image of a pattern onto the substrate through the projection optical system of the exposure apparatus as defined in claim 20; and

processing the exposed substrate to produce the device.

24. An exposure apparatus which exposes a substrate by projecting an image of a pattern onto the substrate through a liquid, the exposure apparatus comprising:

a projection optical system which projects the image of the pattern onto the substrate;

a substrate stage which has a substrate holder to hold the substrate and which is movable;

a detector which detects whether or not the substrate or a dummy substrate is held by the substrate holder; and

a control unit which changes a movable area of the substrate stage depending on a detection result obtained by the detector.

25. The exposure apparatus according to claim 24, further comprising a nozzle member which has at least any one of a supply port to supply the liquid and a recovery port to recover the liquid, wherein the control unit sets the movable area of the substrate stage so that the substrate holder is not positioned under the nozzle member when the detector does not detect the substrate or the dummy substrate is held by the substrate holder.

26. The exposure apparatus according to claim 25, further comprising a liquid supply system which supplies the liquid to the nozzle member, wherein the control unit stops supply of the liquid by the liquid supply system when the detector does not detect that the substrate or the dummy substrate is held by the substrate holder.

27. The exposure apparatus according to claim 24, further comprising a substrate-attracting and holding system which attracts the substrate to the substrate holder, wherein the detector is a pressure detector which is in fluid communication with the substrate-attracting and holding system.

28. The exposure apparatus according to claim 24, further comprising a storage portion on which the dummy substrate is placed.

29. A method for producing a device, the method comprising:

exposing a substrate by projecting an image of a pattern onto the substrate through the projection optical system of the exposure apparatus as defined in claim 24; and

processing the exposed substrate to produce the device.

30. The exposure apparatus according to claim 24, wherein the dummy substrate has a shape and a size which are approximately same as those of the substrate, the substrate being usable to produce a device.

31. An exposure apparatus which exposes a substrate by projecting an image of a pattern onto the substrate through a liquid, the exposure apparatus comprising:

a projection optical system which projects the image of the pattern onto the substrate;

a substrate stage which has a substrate holder to hold the substrate and which is movable;

a liquid supply system which supplies the liquid;

a detector which detects whether or not the substrate or a dummy substrate is held by the substrate holder; and

a control unit which controls operation of the liquid supply system on the basis of a detection result obtained by the detector.

32. The exposure apparatus according to claim 31, further comprising a substrate-attracting and holding system which attracts the substrate to the substrate holder, wherein the detector is a pressure detector which is in fluid communication with the substrate-attracting and holding system.

33. The exposure apparatus according to claim 31, further comprising a storage portion on which the dummy substrate is placed.

34. A method for producing a device, the method comprising:

exposing a substrate by projecting an image of a pattern onto the substrate through the projection optical system of the exposure apparatus as defined in claim 31; and

processing the exposed substrate to produce the device.

35. The exposure apparatus according to claim 31, wherein the dummy substrate has a shape and a size which are approximately same as those of the substrate, the substrate being usable to produce a device.

36. The exposure apparatus according to claim 31, wherein

the liquid supply system includes a liquid flow passage via which the liquid is supplied onto the substrate stage, and an opening/closing mechanism which is arranged on the liquid flow passage and opens and closes the liquid flow passage, and

the control unit controls the opening/closing mechanism based on a detection result obtained by the detector.

37. An exposure apparatus which exposes a substrate by projecting an image of a pattern onto the substrate through a liquid, the exposure apparatus comprising:

a projection optical system which projects the image of the pattern onto the substrate;

a substrate stage which has a substrate holder to hold the substrate and which is movable;

a liquid supply system which supplies the liquid, and

a control unit connected to the substrate stage and the liquid supply system, the control unit controls the liquid supply system to supply the liquid onto the substrate stage under a condition of receiving information that the substrate or a dummy substrate is held by the substrate holder, wherein the dummy substrate is an alternative of the substrate.

38. The exposure apparatus according to claim 37, further comprising a storage portion on which the dummy substrate is placed.

39. A method for producing a device, the method comprising:

exposing a substrate by projecting an image of a pattern onto the substrate through the projection optical system of the exposure apparatus as defined in claim 37; and

processing the exposed substrate to produce the device.

40. The exposure apparatus according to claim 37, wherein when the substrate or the dummy substrate is not held by the substrate holder, the control unit prohibits the supply of the liquid onto the substrate stage by the liquid supply system.

41. The exposure apparatus according to claim 37, further comprising a detector which detects whether or not the substrate or the dummy substrate is held by the substrate holder.

42. The exposure apparatus according to claim 37, wherein the dummy substrate has a shape and a size which are approximately same as those of the substrate, the substrate being usable to produce a device.

43. The exposure apparatus according to claim 37, wherein

the liquid supply system includes a liquid flow passage for supplying the liquid onto the substrate stage, and an opening/closing mechanism which is arranged on the liquid flow passage and opens and closes the liquid flow passage, and

the control unit controls the opening/closing mechanism to open the liquid flow passage only when the substrate or the dummy substrate is held by the substrate holder.

44. An exposure apparatus which exposes a substrate by projecting an image of a pattern onto the substrate through a liquid, the exposure apparatus comprising:

a projection optical system which projects the image of the pattern onto the substrate;

a substrate stage which is movable;

a liquid immersion system which forms a liquid immersion area; and

a control unit connected to the substate stage and the liquid immersion area on the substrate stage under a condition of receiving information that the substrate or a dummy substrate is held by the substrate stage, wherein the dummy substrate is an alternative of the substrate.

45. The exposure apparatus according to claim 44, wherein the substrate stage has a flat portion which is disposed around the substrate or the dummy substrate held by the substrate stage and which is substantially flush with a surface of the substrate or the dummy substrate held by the substrate stage.

46. The exposure apparatus according to claim 45, further comprising a measuring member which is arranged on the flat portion of the substrate stage, and a detecting system which detects a light beam from the measuring member in a state in which the liquid immersion area is formed on at least a part of a surface of the measuring member.

47. The exposure apparatus according to claim 44, wherein the substrate stage has a recess in which the substrate is arrangeable and a flat portion arranged around the recess, and the flat portion is substantially flush with a surface of the substrate and a surface of the dummy substrate arranged in the recess.

48. The exposure apparatus according to claim 47, wherein the control unit prohibits formation of the liquid immersion area on the substrate stage when the substrate or the dummy substrate is not arranged in the recess.

49. The exposure apparatus according to claim 48, wherein the control unit stops supply of the liquid by the liquid immersion system when the substrate or the dummy substrate is not arranged in th recess.

50. The exposure apparatus according to claim 48, wherein the control unit controls movement of the substrate stage so that the substrate stage is not opposed to an optical element disposed at a terminal end of the projection optical system when neither the substrate nor the dummy substrate is arranged in the recess.

51. A method for producing a device, the method comprising:

exposing a substrate by projecting an image of a pattern onto the substrate through the projection optical system of the exposure apparatus as defined in claim 47; and

processing the exposed substrate to produce the device.

52. The exposure apparatus according to claim 47, further comprising a holding member which holds the object in the recess;

and

a lifting mechanism which moves the holding member upwardly and downwardly in the recess,

wherein the liquid immersion area is formed on the substrate stage when a surface of the holding member, which is moved upwardly in the recess, is substantially flush with the flat portion.

53. The exposure apparatus according to claim 44, further comprising a storage portion on which the dummy substrate is placed.

54. A method for producing a device, the method comprising:

exposing a substrate by projecting an image of a pattern onto the substrate through the projection optical system of the exposure apparatus as defined in claim 44; and

processing the exposed substrate to produce the device.

55. The exposure apparatus according to claim 44, wherein when the substrate or the dummy substrate is not held by the substrate stage, the control unit prohibits a formation of the liquid immersion area on the substrate stage.

56. The exposure apparatus according to claim 44, further comprising a detector which detects whether or not the substrate or the dummy substrate is held by the substrate stage.

57. The exposure apparatus according to claim 44, further comprising an alignment mechanism which detects an alignment mark on the substrate held by the substrate stage,

wherein the liquid immersion system forms the liquid immersion area on the substrate stage after the alignment mechanism detects the alignment mark.

58. The exposure apparatus according to claim 44, further comprising a height-detecting system which detects a position information in a height direction of the substrate or the dummy substrate held by the substrate stage,

wherein the liquid immersion system forms the liquid immersion area on the substrate stage after the height-detecting system detects the position information in the height direction of the substrate or the dummy substrate.

59. The exposure apparatus according to claim 44, wherein the dummy substrate has a shape and a size which are approximately same as those of the substrate, the substrate being usable to produce a device.

60. The exposure apparatus according to claim 44, wherein

the liquid immersion system includes a liquid supply mechanism having a liquid flow passage via which the liquid is supplied onto the substrate stage, and an opening/closing mechanism which is arranged on the liquid flow passage and opens and closes the liquid flow passage, and

the control unit controls the opening/closing mechanism to open the liquid flow passage only when the substrate or the dummy substrate is held by the substrate holder.

61. An exposure apparatus which exposes a substrate by projecting an image of a pattern onto the substrate through a liquid, the exposure apparatus comprising:

a projection optical system which projects the image of the pattern onto the substrate;

a stage which is movable on an image plane side of the projection optical system;

a first detecting system which detects an alignment mark on the substrate and which detects a first reference provided on the stage; and

a second detecting system which detects a second reference provided on the stage via the projection optical system, wherein;

the first reference provided on the stage is detected not through the liquid by using the first detecting system, and the second reference provided on the stage is detected via the projection optical system and the liquid by using the second detecting system to determine a positional relationship between a detection reference position of the first detecting system and a projection position of the image of the pattern.

62. A method for producing a device, the method comprising:

exposing a substrate by projecting an image of a pattern onto the substrate through the projection optical system of the exposure apparatus as defined in claim 61; and

processing the exposed substrate to produce the device.

63. An exposure method for exposing a substrate by projecting an image of a pattern onto the substrate via a projection optical system and a liquid, the exposure method comprising:

detecting position information about an alignment mark on the substrate by using a first detecting system;

detecting position information about a first reference on a substrate stage which holds the substrate, by using the first detecting system; and

detecting a second reference on the substrate stage via the projection optical system and the liquid by using a second detecting system after completion of both of detection of the position information about the alignment mark and detection of the position information about the first reference on the substrate stage by the first detecting system,

wherein;

a relationship between a detection reference position of the first detecting system and a projection position of the image of the pattern is determined on the basis of a detection result of the position information about the alignment mark obtained by the first detecting system, a detection result of the position information about the first reference on the substrate stage obtained by the first detecting system, and a detection result of the position information about the second reference on the substrate stage obtained by the second detecting system, and the image of the pattern and the substrate are relatively moved to successively project the image of the pattern onto each of a plurality of shot areas on the substrate to expose the substrate.

64. The exposure method according to claim 63, wherein position information about an alignment mark on another substrate is detected by using the first detecting system without detecting the position information about the first reference on the substrate stage when the another substrate is held and exposed on the substrate stage after completion of exposure of the substrate, and the image of the pattern is successfully projected onto each of a plurality of shot areas on the another substrate to expose the another substrate on the basis of the position information about the alignment mark on the another substrate detected by using the first detecting system and the relationship between the detection reference position of the first detecting system and the projection position of the image of the pattern.

65. The exposure method according to claim 63, wherein the first reference and the second reference are arranged separately from each other in a predetermined positional relationship.

66. The exposure method according to claim 63, wherein detection of the position information about the first reference on the substrate stage by the first detecting system and detection of the position information about the second reference on the substrate stage by the second detecting system are performed in a state in which the substrate is held by the substrate stage after completion of exposure of the substrate, and the substrate is exported from the substrate stage after completion of the detection.

67. A method for producing a device, comprising using the exposure method as defined in claim 63.

68. An exposure apparatus which exposes a substrate by projecting an image of a pattern onto the substrate through a liquid, the exposure apparatus comprising:

a projection optical system which projects the image of the pattern onto the substrate;

a substrate stage which has a substrate holder to hold the substrate and which is movable; and

a control unit connected to the substrate stage, the control unit prohibits formation of a liquid immersion area on the substrate stage under a condition of receiving information that the substrate or a dummy substrate is not held by the holder.

69. The exposure apparatus according to claim 68, further comprising a detector which detects whether or not the substrate or a dummy substrate is held by the substrate holder.

70. The exposure apparatus according to claim 68, further comprising a detector which detects a mark through the liquid immersion area formed on the substrate stage.

71. The exposure apparatus according to claim 68, wherein the projection optical system projects the image of the pattern through the liquid immersion area formed on the substrate stage.

72. A method for producing a device, comprising using the exposure apparatus as defined in claim 68.