Movable body drive method and apparatus, exposure method and apparatus, pattern formation method and apparatus, and device manufacturing method

• US 8,269,945 B2
• Filed: 12/24/2008
• Issued: 09/18/2012
• Est. Priority Date: 12/28/2007
• Status: Expired due to Fees

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: Shibazaki, Yuichi
• Primary Examiner(s): Nguyen, Hung Henry
• Assistant Examiner(s): Whitesell Gordon, Steven H
• Application Number:
  US12/343,751
• Publication Number:
  US 20090190104A1
• Time in Patent Office: 1,364 Days
• Field of Search: 355/30, 355/53, 355/72, 355/75
• US Class Current: 355/30
• CPC Class Codes: G03F 7/70775 Position control, e.g. interferometers or encoders for determining the stage position

Abstract

Encoder heads and Z heads are installed in order to measure the position of a stage that moves within a predetermined plane. Measurement beams emitted from these heads are irradiated to scales arranged on the upper surface of the stage. During the idling, for example, the stage continues to be moved by driving and rotating the stage around the stop position of the stage serving as the center, or the stage is withdrawn to an area to which the measurement beams are not irradiated.

Claims

1. A movable body drive method of driving a movable body within a predetermined plane, the method comprising:

a process of driving the movable body based on a result obtained by measuring a position of the movable body using a position measuring system that comprises a head that irradiates a measurement surface with a measurement beam, the measurement surface being installed on one of the movable body and an external of the movable body, and the head being installed on the other of the movable body and the external of the movable body; and

a process of adjusting an irradiation amount of the measurement beam onto the measurement surface so that an accumulated amount of heat on the measurement surface does not exceed a predetermined level.

2. The movable body drive method according to claim 1, wherein

in the process of adjusting, the irradiation amount of the measurement beam onto the measurement surface is adjusted by driving the movable body.

3. The movable body drive method according to claim 2, wherein

in the process of adjusting, the movable body continues to be moved within a predetermined range.

4. The movable body drive method according to claim 2, wherein

in the process of adjusting, the movable body is driven at a speed with which an amount of the measurement beam that is absorbed by the measurement surface does not exceed a constant amount.

5. The movable body drive method according to claim 4, wherein

the constant amount is set based on at least one of a thermal stress and a deformation quantity at the measurement surface that are generated due to the measurement beam being absorbed.

6. The movable body drive method according to claim 1, wherein

in the process of adjusting, the movable body is withdrawn to an area with which an irradiation point of the measurement beam is located outside the measurement surface.

7. The movable body drive method according to claim 1, wherein

in the process of adjusting, the measurement beam is intermittently irradiated from a head that faces the measurement surface.

8. The movable body drive method according to claim 1, wherein

in the process of adjusting, the measurement beam whose intensity is decreased is irradiated from a head that faces the measurement surface.

9. An exposure method of forming a pattern on a divided area on an object by irradiating the object with an energy beam, the method comprising:

a process of driving a movable body that holds the object by using the movable body drive method according to claim 1, to form a pattern on the divided area.

10. A pattern formation method of forming a pattern on an object, the method comprising:

a process of driving a movable body that holds the object by using the movable body drive method according to claim 1, to form a pattern on the object.

11. The pattern formation method according to claim 10, wherein

the object has a sensitive layer, and

the pattern is formed by irradiating the sensitive layer with an energy beam.

12. A device manufacturing method, comprising:

a process of forming a pattern on an object by using the pattern formation method according to claim 10; and

a process of applying processing to the object on which the pattern has been formed.

13. The exposure method according to claim 1, wherein

in the process of adjusting, a light-shielding member is placed in an optical path of the measurement beam.

14. The exposure method according to claim 1, wherein

in the process of adjusting, the movable body is moved to a predetermined position at which a cover to cover the measurement surface is installed.

15. The exposure method according to claim 14, wherein

a plurality of the heads are provided, and

the predetermined position is a position at which the measurement beam from at least one of the plurality of the heads is irradiated on the measurement surface.

16. The exposure method according to claim 14, wherein

a plurality of the heads are provided, and

the cover shields the measurement beam only to a head of the plurality of the heads that faces the measurement surface.

17. An exposure method of exposing an object with an energy beam, the method comprising:

driving a movable body that can move within a predetermined plane while holding the object based on positional information of the movable body, the positional information being measured by using a position measuring system that has a measurement surface installed on one of the movable body and an external thereof, and a head installed on the other; and

blocking a physical quantity that includes at least one of a thermal stress and a deformation quantity at the measurement surface from exceeding a permissible value due to irradiation of the measurement beam by adjusting an irradiation amount of the measurement beam onto the measurement surface.

18. The exposure method according to claim 17, wherein

the measurement surface is substantially parallel to the predetermined plane and has a diffraction grating.

19. The exposure method according to claim 17, wherein

for the blocking, the movable body is driven within the predetermined plane.

20. The exposure method according to claim 17, wherein

for the blocking, the measurement surface is made to be out of an irradiation point of the measurement beam.

21. The exposure method according to claim 17, wherein

for the blocking, a light-shielding member is placed in an optical path of the measurement beam, or intensity of the measurement beam is decreased.

22. The exposure method according to claim 17, wherein

the blocking is performed during at least one of the time of abnormality in an exposure sequence of the object and a period when the movable body is not used

23. The exposure method according to claim 17, further comprising:

measuring positional information of the object with another measurement device that is separate from the position measuring system; and

blocking the physical quantity from exceeding a permissible value due to irradiation of a beam of the measurement device.

24. A device manufacturing method, comprising:

exposing an object by using the exposure method according to claim 17; and

developing the object that has been exposed.

25. The exposure method according to claim 18, wherein

for the blocking, the movable body is moved to a predetermined position at which a cover to cover the diffraction grating is installed.

26. The exposure method according to claim 25, wherein

a plurality of the heads are provided, and

the predetermined position is a position at which the measurement beam from at least one of the plurality of the heads is irradiated on the diffraction grating.

27. The exposure method according to claim 25, wherein

a plurality of the heads are provided, and

the cover shields the measurement beam only to a head of the plurality of the heads that faces the diffraction grating.

28. The exposure method according to claim 25, wherein

the cover covers a part of the diffraction grating.

29. A movable body drive apparatus that drives a movable body within a predetermined plane, the apparatus comprising:

a position measuring system that measures a position of the movable body by using a head that irradiates a measurement surface with a measurement beam, the measurement surface being installed on one of the movable body and an external of the movable body, and the head being installed on the other of the movable body and the external of the movable body;

a drive device that drives the movable body within the predetermined plane based on a measurement result of the position measuring system; and

an adjustment device that adjusts an irradiation amount of the measurement beam onto the measurement surface so that an accumulated amount of heat on the measurement surface does not exceed a predetermined level.

30. The movable body drive apparatus according to claim 29, wherein

the adjustment device continues to move the movable body within a predetermined range.

31. The movable body drive apparatus according to claim 29, wherein

the adjustment device drives the movable body at a speed with which an amount of the measurement beam that is absorbed by the measurement surface does not exceed a constant amount.

32. The movable body drive apparatus according to claim 31, wherein

the constant amount is set based on at least one of a thermal stress and a deformation quantity at the measurement surface that are generated due to the measurement beam being absorbed.

33. The movable body drive apparatus according to claim 29, wherein

the adjustment device withdraws the movable body to an area with which an irradiation point of the measurement beam is located outside the measurement surface.

34. The movable body drive apparatus according to claim 29, wherein

on the measurement surface, a diffraction grating having a periodic direction in a direction parallel to a first axis within the predetermined plane is formed, and

the position measuring system includes an encoder system that measures a relative position in the direction parallel to the first axis of the measurement surface and the head that irradiates the measurement surface with the measurement beam.

35. The movable body drive apparatus according to claim 34, wherein

on the measurement surface, another diffraction grating having a periodic direction in a direction parallel to a second axis that is orthogonal to the first axis within the predetermined plane is further formed, and

the encoder system further measures a relative position in the direction parallel to the second axis of the measurement surface and the head.

36. The movable body drive apparatus according to claim 29, wherein

the position measuring system includes a surface position measuring system that measures a position of the measurement surface in a direction orthogonal to the predetermine plane, at an irradiation point of the measurement beam.

37. The movable body drive apparatus according to claim 29, wherein

the position measuring system includes a mark detecting system that detects a mark on the measurement surface by using the head.

38. An exposure apparatus that forms a pattern on a divided area on an object by irradiating the object with an energy beam, the apparatus comprising:

the movable body drive apparatus according to claim 29 that drives a movable body that holds the object within a predetermined plane, to form a pattern on the divided area.

39. A pattern formation apparatus that forms a pattern on an object, the apparatus comprising:

a movable body that can move while holding the object;

a pattern generating device that forms a pattern on the object; and

the movable body drive apparatus according to claim 29 that drives the movable body within a predetermined plane.

40. The pattern formation apparatus according to claim 39, wherein

the object has a sensitive layer, and

the pattern generating device forms the pattern by irradiating the sensitive layer with an energy beam.

41. An exposure apparatus that exposes an object with an energy beam, the apparatus comprising:

a movable body that can move within a predetermined plane, while holding the object;

a position measuring system that has a head and measures positional information of the movable body by irradiating a measurement surface with a measurement beam from the head and receiving a reflected light of the measurement beam, the measurement surface being installed on one of the movable body and an external of the movable body, and a head being installed on the other of the movable body and the external of the movable body;

a drive system that drives the movable body based on the positional information; and

a controller that blocks a physical quantity that includes at least one of a thermal stress and a deformation quantity at the measurement surface from exceeding a permissible value due to irradiation of the measurement beam by adjusting an irradiation amount of the measurement beam onto the measurement surface.

42. The exposure apparatus according to claim 41, wherein

the measurement surface is substantially parallel to the predetermined plane and has a diffraction grating.

43. The exposure apparatus according to claim 41, wherein

for the blocking, the controller drives the movable body within the predetermined plane via the drive system.

44. The exposure apparatus according to claim 41, wherein

for the blocking, the controller makes the measurement surface be out of an irradiation point of the measurement beam.

45. The exposure apparatus according to claim 41, wherein

for the blocking, the controller places a light-shielding member in an optical path of the measurement beam, or decreases intensity of the measurement beam.

46. The exposure apparatus according to claim 41, wherein

the controller performs the blocking during at least one of the time of abnormality in an exposure sequence of the object and a period when the movable body is not used.

47. The exposure apparatus according to claim 41, further comprising:

another measurement device that measures positional information of the object and is separate from the position measuring system;

wherein

the controller blocks the physical quantity from exceeding a permissible value due to irradiation of a beam of the measurement device.

48. A device manufacturing method, comprising:

exposing an object by using the exposure apparatus according to claim 41; and

developing the object that has been exposed.