MOVABLE BODY DRIVE METHOD AND MOVABLE BODY DRIVE SYSTEM, PATTERN FORMATION METHOD AND APPARATUS, EXPOSURE METHOD AND APPARATUS, AND DEVICE MANUFACTURING METHOD

• US 20090053629A1
• Filed: 08/21/2008
• Published: 02/26/2009
• Est. Priority Date: 08/24/2007
• Status: Active Grant

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: SHIBAZAKI, Yuichi, KANAYA, Yuho
• Granted Patent: US 8,023,106 B2
• Time in Patent Office: Days
• US Class Current: 430/30
• CPC Class Codes: G03F 7/70775 Position control, e.g. interferometers or encoders for determining the stage position

Abstract

Positional information of a wafer stage in a Z-axis direction and a tilt direction with respect to the XY plane (for example, a θy direction) is measured, using a surface position measurement system, such as, for example, a Z head and the like, and the wafer stage is driven based on the measurement results.

At the same time, positional information of the wafer stage is measured using an interferometer system such as, for example, a Z interferometer. When abnormality of the surface position measurement system is detected or when the wafer stage moves off from a measurement area of the surface position measurement system, drive control is switched to a drive control based on the measurement results of the interferometer system. Accordingly, the wafer stage can be driven continuously even at the time of abnormality generation in the surface position measurement system.

Claims

1. A movable body drive method in which a movable body is driven substantially along a two-dimensional plane, the method comprising:

a first process in which positional information of the movable body related to at least one of a direction perpendicular to the two-dimensional plane and a tilt direction with respect to the two-dimensional plane is detected, using a first detection device that has one, or more than one detection positions placed in at least a part of an operating area of the movable body, and detects positional information of the movable body in the direction perpendicular to the two-dimensional plane using detection information detected when the movable body is positioned at any one of the detection points, and a second detection device that detects positional information of the movable body in the direction perpendicular to the two-dimensional plane from measurement results using a measurement beam irradiated along the two-dimensional plane between the outside of the operating area of the movable body and the movable body, and the movable body is driven in at least one of the direction perpendicular to the two-dimensional plane and the tilt direction with respect to the two-dimensional plane based on detection results of the first detection device;

a second process in which relation information between a first positional information of the movable body computed from detection information of the first detection device and a second positional information of the movable body computed from detection in formation of the second detection device is updated at every predetermined timing; and

a third process in which when abnormality occurring in an output of the first detection device has been detected, the detection device used for drive control of the movable body in at least one of the direction perpendicular to the two-dimensional plane and the tilt direction with respect to the two-dimensional plane is switched from the first detection device to the second detection device.

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

in the third process, the detection devices is switched from the first detection device to the second detection device whose second position coordinate has been corrected, so that the second position coordinate of the movable body in an n^th order coordinate system computed from detection information of the first detection device just before becomes successive to a first position coordinate computed from the detection information of the movable body in at least a direction of one degree of freedom in the n^th order coordinate system (n is a natural number of three or less), among a direction perpendicular to the two-dimensional plane and rotational directions around two axes orthogonal to the two-dimensional plane.

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

the relation information is offset information associated with a difference between the first position coordinate and the second position coordinate of the movable body.

4. The movable body drive method according to claim 3 wherein

the relation information is a moving average regarding a predetermined number of control clocks of the difference.

5. The movable body drive method according to claim 1, the method further comprising:

an inspection process in which reliability of the detection information of the first detection device is inspected, using the relation information.

6. The movable body drive method according to claim 5 wherein

in the third process, when abnormality that has occurred in the output of the first detection device has been detected, the second positional information of the movable body computed by the detection information of the second detection device at the time of occurrence is corrected, using the relation information which has been confirmed normal at the time of a preceding inspection.

7. The movable body drive method according to claim 1, the method further comprising:

a return process in which the detection device used for drive control of the movable body in at least one of the direction perpendicular to the two-dimensional plane and the tilt direction with respect to the two-dimensional plane is returned from the second detection device to the first detection device at a predetermined timing, when the movable body is driven in at least one of the direction perpendicular to the two-dimensional plane and the tilt direction with respect to the two-dimensional plane based on the detection results of the second detection device.

8. The movable body drive method according to claim 7 wherein

reliability of the detection information of the first detection device is inspected using the relation information, and as a result of the inspection, when the reliability has been confirmed, return from the second detection device to the first detection device is performed.

9. The movable body drive method according to claim 1 wherein

the abnormality is absence of output from the first detection device, or the output from the first detection device exceeding a predetermined threshold value.

10. The movable body drive method according to claim 1 wherein

as the first detection device, a detection device is used that has a plurality of sensor heads detecting positional information of a surface of the movable body substantially parallel to the two-dimensional plane in a direction perpendicular to the two-dimensional plane, with a reference plane parallel to the two-dimensional plane serving as a reference, when the movable body is positioned at each detection position in a plurality of different detection positions within an operating area of the movable body, and each sensor head includes a first sensor including a movable member which moves to maintain an optical positional relation with a measurement subject according to a positional change of the movable member in the direction perpendicular to the two-dimensional plane when the surface of the movable body is located at each detection position, and a second sensor which detects the displacement of the movable member from a reference point.

11. A pattern formation method to form a pattern on an object wherein

a movable body on which the object is mounted is driven using the movable body drive method according to claim 1 to perform pattern formation to the object.

12. The pattern formation method according to claim 11 wherein

the object has a sensitive layer, and a pattern is formed on the object by an exposure of the sensitive layer by irradiation of an energy beam.

13. A device manufacturing method including a pattern formation process wherein

in the pattern formation process, a pattern is formed on a substrate using the pattern formation method according to claim 11.

14. An exposure method in which a pattern is formed on an object by an irradiation of an energy beam wherein

for relative movement of the energy beam and the object, a movable body on which the object is mounted is driven, using the movable body drive method according to claim 1.

15. A movable body drive method in which a movable body is driven substantially along a two-dimensional plane, the method comprising:

a first process in which positional information of the movable body in directions of three degrees of freedom within a plane parallel to the two-dimensional plane is detected, using a first detection device which detects positional information in directions of three degrees of freedom within the plane parallel to the two-dimensional plane from measurement results using a measurement beam irradiated along the two-dimensional plane between the outside of the operating area of the movable body and the movable body, and positional information of the movable body in a direction perpendicular to the two-dimensional plane and a tilt direction with respect to the two-dimensional plane is also detected, using a second detection device which detects positional information of the movable body in a direction perpendicular to the two-dimensional plane and a tilt direction with respect to the two-dimensional plane from measurement results using a measurement beam irradiated along the two-dimensional plane between the outside of the operating area of the movable body and the movable body; and

a second process in which on switching from servo control of the position in the directions of three degrees of freedom of the movable body using the first detection device to servo control of the position in the directions of three degrees of freedom of the movable body using an encoder system, a detection device that detects positional information of the movable body in the direction perpendicular to the two-dimensional plane and the tilt direction around at least one axis with respect to the two-dimensional plane is switched from the second detection device when the movable body is in a suspended state, to a third detection device that has a plurality of detection positions placed in at least a part of an operating area of the movable body, and detects positional information of the movable body in the direction perpendicular to the two-dimensional plane using detection information detected when the movable body is positioned at any one of the detection positions.

16. The movable body drive method according to claim 15 wherein

as the third detection device, a detection device is used that has a plurality of sensor heads detecting positional information of a surface of the movable body substantially parallel to the two-dimensional plane in a direction perpendicular to the two-dimensional plane, with a reference plane parallel to the two-dimensional plane serving as a reference, when the movable body is positioned at each detection position in a plurality of different detection positions within an operating area of the movable body, and each sensor head includes a first sensor including a movable member which moves to maintain an optical positional relation with a measurement subject according to a positional change of the movable member in the direction perpendicular to the two-dimensional plane when the surface of the movable body is located at each detection position, and a second sensor which detects the displacement of the movable member from a reference point.

17. A pattern formation method to form a pattern on an object wherein

a movable body on which the object is mounted is driven using the movable body drive method according to claim 15 to perform pattern formation to the object.

18. The pattern formation method according to claim 17 wherein

the object has a sensitive layer, and a pattern is formed on the object by an exposure of the sensitive layer by irradiation of an energy beam.

19. A device manufacturing method including a pattern formation process wherein

in the pattern formation process, a pattern is formed on a substrate using the pattern formation method according to claim 17.

20. An exposure method in which a pattern is formed on an object by an irradiation of an energy beam wherein

for relative movement of the energy beam and the object, a movable body on which the object is mounted is driven, using the movable body drive method according to claim 15.

21. A movable body drive method in which a movable body is driven substantially along a two-dimensional plane, the method comprising:

a first process in which the movable body is driven based on an output of a first detection device that has a plurality of detection positions placed in at least a part of an operating area of the movable body, and detects positional information of the movable body in a direction perpendicular to the two-dimensional plane using detection information detected when the movable body is positioned at any one of the detection positions, and the output of an encoder system that measures positional information of the movable body within a plane parallel to the two-dimensional plane in directions of three degrees of freedom; and

a second process in which in the case of switching from servo control of the position of the movable body in the directions of three degrees of freedom using the encoder system, to a control of the position of the movable body in the directions of three degrees of freedom using a second detection device that detects positional information in directions of three degrees of freedom within a plane parallel to the two-dimensional plane from measurement results using a measurement beam irradiated along the two-dimensional plane between the outside of the operating are of the movable body and the movable body, a detection device used for control of the position of the movable body in the remaining directions of three degrees of freedom is switched from the first detection device to a third detection device that detects positional information of the movable body in the direction perpendicular to the two-dimensional plane and a tilt direction with respect to the two-dimensional plane from measurement results using a measurement beam irradiated along the two-dimensional plane between the outside of the operating area of the movable body and the movable body at the point where the movable body is suspended.

22. The movable body drive method according to claim 21 wherein

as the first detection device, a detection device is used that has a plurality of sensor heads detecting positional information of a surface of the movable body substantially parallel to the two-dimensional plane in a direction perpendicular to the two-dimensional planer with a reference plane parallel to the two-dimensional plane serving as a reference, when the movable body is positioned at each detection position in a plurality of different detection positions within an operating area of the movable body, and each sensor head includes a first sensor including a movable member which moves to maintain an optical positional relation with a measurement subject according to a positional change of the movable member in the direction perpendicular to the two-dimensional plane when the surface of the movable body is located at each detection position, and a second sensor which detects the displacement of the movable member from a reference point.

23. The movable body drive method according to claim 21 wherein

the first detection device has a plurality of sensor heads detecting positional information of a surface of the movable body substantially parallel to the two-dimensional plane in a direction perpendicular to the two-dimensional plane, with a reference plane parallel to the two-dimensional plane serving as a reference, when the movable body is positioned at each detection position in a plurality of different detection positions within an operating area of the movable body, and each sensor head includes a first sensor including a movable member which moves to maintain an optical positional relation with a measurement subject according to a positional change of the movable member in the direction perpendicular to the two-dimensional plane when the surface of the movable body is located at each detection position, and a second sensor which detects the displacement of the movable member from a reference point.

24. A pattern formation method to form a pattern on an object wherein

a movable body on which the object is mounted is driven using the movable body drive method according to claim 21 to perform pattern formation to the object.

25. The pattern formation method according to claim 24 wherein

the object has a sensitive layer, and a pattern is formed on the object by an exposure of the sensitive layer by irradiation of an energy beam.

26. A device manufacturing method including a pattern formation process wherein

in the pattern formation process, a pattern is formed on a substrate using the pattern formation method according to claim 24.

27. An exposure method in which a pattern is formed on, an object by an irradiation of an energy beam wherein

for relative movement of the energy beam and the object, a movable body on which the object is mounted is driven, using the movable body drive method according to claim 21.

28. A movable body drive system in which a movable body is driven substantially along a two-dimensional plane, the system comprising:

a first detection device that has ones or more than one detection positions placed in at least a part of an operating area of the movable body, and detects positional information of the movable body in a direction perpendicular to the two-dimensional plane using detection information detected when the movable body is positioned at any one of the detection points;

a second detection device that detects positional information of the movable body in the direction perpendicular to the two-dimensional plane from measurement results using a measurement beam irradiated along the two-dimensional plane between the outside of the operating area of the movable body and the movable body; and

a controller that drives the movable body at least one of a direction perpendicular to the two-dimensional plane and a tilt direction with respect to the two-dimensional plane based on detection results of the first detection device, and also updates relation information between a first positional information of the movable body computed from detection information of the first detection device and a second positional information of the movable body computed from detection information of the second detection device at every predetermined timing, and when abnormality occurring in the output of the first detection device is detected, switches a detection device used for drive control of at least one of the direction perpendicular to the two-dimensional plane and a tilt direction with respect to the two-dimensional plane from the first detection device to the second detection device.

29. The movable body drive system according to claim 28 wherein

the controller performs switching from the first detection device to the second detection device whose second position coordinate has been corrected, so that the second position coordinate of the movable body in an n^th order coordinate system computed from detection information of the first detection device just before becomes successive to a first position coordinate computed from the detection information of the movable body in at least a direction of one degree of freedom in the n^th order coordinate system (n is a natural number of three or less), among a direction perpendicular to the two-dimensional plane and rotational directions around two axes orthogonal to the two-dimensional plane.

30. The movable body drive system according to claim 29 wherein

the relation information is offset information associated with a difference between the first position coordinate and the second position coordinate of the movable, body.

31. The movable body drive system according to claim 30 wherein

the relation information is a moving average regarding a predetermined number of control clocks of the difference.

32. The movable body drive system according to claim 28 wherein

the controller inspects reliability of the detection information of the first detection device, using the relation information.

33. The movable body drive system according to claim 32 wherein

when abnormality that has occurred in the output of the first detection device has been detected, the controller corrects the second positional information of the movable body computed by the detection information of the second detection device at the time of occurrence, using the relation information which has been confirmed normal at the time of a preceding inspection.

34. The movable body drive system according to claim 28 wherein

the controller returns the detection device used for drive control of the movable body in at least one of the direction perpendicular to the two-dimensional plane and the tilt direction with respect to the two-dimensional plane from the second detection device to the first detection device at a predetermined timing, when the movable body is driven in at least one of the direction perpendicular to the two-dimensional plane and the tilt direction with respect to the two-dimensional plane based on the detection results of the second detection device.

35. The movable body drive system according to claim 34 wherein

the controller inspects reliability of the detection information of the first detection device using the relation information, and as a result of the inspection, when the reliability has been confirmed, performs return from the second detection device to the first detection device.

36. The movable body drive system according to claim 28 wherein

the abnormality is absence of output from the first detection device, or the output from the first detection device exceeding a predetermined threshold value.

37. The movable body drive system according to claim 28 wherein

the first detection device has a plurality of sensor heads detecting positional information of a surface of the movable body substantially parallel to the two-dimensional plane in a direction perpendicular to the two-dimensional plane, with a reference plane parallel to the two-dimensional plane serving as a reference, when the movable body is positioned at each detection position in a plurality of different detection positions within an operating area of the movable body, and each sensor head includes a first sensor including a movable member which moves to maintain an optical positional relation with a measurement subject according to a positional change of the movable member in the direction perpendicular to the two-dimensional plane when the surface of the movable body is located at each detection position, and a second sensor which detects the displacement of the movable member from a reference point.

38. A pattern forming apparatus that forms a pattern on an object, the apparatus comprising:

a patterning device which generates a pattern on the object; and

a movable body drive system according to claim 29, wherein

drive of a movable body on which the object is mounted is performed by the movable body drive system for pattern formation with respect to the object.

39. The pattern formation apparatus according to claim 38 wherein

the object has a sensitive layer, and the patterning device generates a pattern on the object by an exposure of the sensitive layer by irradiation of an energy beam.

40. An exposure apparatus that forms a pattern on an object by an irradiation of an energy beam, the apparatus comprising:

a patterning device that irradiates the energy beam on the object; and

a movable body drive system according to claim 28, wherein

the movable body drive system drives the movable body on which the object is mounted for relative movement of the energy beam and the object.

41. A movable body drive system in which a movable body is driven along a substantially two-dimensional plane, the system comprising:

a first detection device that has a plurality of detection positions placed in at least a part of an operating area of the movable body, and detects positional information of the movable body in a direction perpendicular to the two-dimensional plane using detection information detected when the movable body is positioned at any one of the detection points;

an encoder system that measures positional information of the movable body in directions of three degrees of freedom;

a second detection device that detects positional information of the movable body in directions of three degrees of freedom within a plane parallel to the two-dimensional plane from measurement results using a measurement beam irradiated along the two-dimensional plane between the outside of the operating area of the movable body and the movable body;

a third detection device that detects positional information of the movable body in a direction perpendicular to the two-dimensional plane and a tilt direction with respect to the two-dimensional plane from measurement results using a measurement beam irradiated along the two-dimensional plane between the outside of the operating area of the movable body and the movable body; and

a controller that switches a detection device which detects positional information of the movable body in the direction perpendicular to the two-dimensional plane and the tilt direction around at least one axis with respect to the two-dimensional plane from the third detection device when the movable body is in a suspended state to the first detection device, on switching from servo control of the position in the directions of three degrees of freedom of the movable body using the second detection device to servo control of the position in the directions of three degrees of freedom of the movable body using the encoder system.

42. The movable body drive system according to claim 41 wherein

the first detection device includes a first sensor which has a plurality of sensor heads detecting positional information of a surface of the movable body substantially parallel to the two-dimensional plane in a direction perpendicular to the two-dimensional plane, with a reference plane parallel to the two-dimensional plane serving as a reference when the movable body is positioned at each detection position in a plurality of different detection positions within an operating area of the movable body, and each sensor head including a movable member that moves to maintain an optical positional relation with a measurement subject according to a positional change of the movable body in the direction perpendicular to the two-dimensional plane when the surface of the movable body is located at each detection position, and a second sensor which detects the displacement of the movable member from a reference point.

43. A pattern forming apparatus that forms a pattern on an object, the apparatus comprising:

a patterning device which generates a pattern on the object; and

a movable body drive system according to claim 42, wherein

drive of a movable body on which the object is mounted is performed by the movable body drive system for pattern formation with respect to the object.

44. The pattern formation apparatus according to claim 43 wherein

the object has a sensitive layer, and the patterning device generates a pattern on the object by an exposure of the sensitive layer by irradiation of an energy beam.

45. An exposure apparatus that forms a pattern on an object by an irradiation of an energy beam, the apparatus comprising:

a patterning device that irradiates the energy beam on the object; and

a movable body drive system according to claim 41, wherein

the movable body drive system drives the movable body on which the object is mounted for relative movement of the energy beam and the object.

46. A movable body drive system in which a movable body is driven along a substantially two-dimensional plane, the system comprising:

a first detection device that has a plurality of detection positions placed in at least a part of an operating area of the movable body, and detects positional information of the movable body in a direction perpendicular to the two-dimensional plane using detection information detected when the movable body is positioned at any one of the detection points;

an encoder system that measures positional information of the movable body within a plane parallel to the two-dimensional plane in directions of three degrees of freedom;

a second detection device that detects positional information of the movable body in directions of three degrees of freedom within a plane parallel to the two-dimensional plane from measurement results using a measurement beam irradiated along the two-dimensional plane between the outside of the operating area of the movable body and the movable body;

a third detection device that detects positional information of the movable body in a direction perpendicular to the two-dimensional plane and a tilt direction with respect to the two-dimensional plane from measurement results using a measurement beam irradiated along the two-dimensional plane between the outside of the operating area of the movable body and the movable body; and

a controller that switches a measurement device used for controlling the position of the movable body in the remaining directions of three degrees of freedom from the first detection device to the third detection device at the point where the movable body is suspended, in the case of switching from servo control of the position of the movable body using the encoder system to control of the position of the movable body in the directions of three degrees of freedom using the second detection device.

47. The movable body drive system according to claim 46 wherein

the first detection device has a plurality of sensor heads detecting positional information of a surface of the movable body substantially parallel to the two-dimensional plane in a direction perpendicular to the two-dimensional plane, with a reference plane parallel to the two-dimensional plane serving as a reference, when the movable body is positioned at each detection position in a plurality of different detection positions within an operating area of the movable body, and each sensor head includes a first sensor including a movable member which moves to maintain an optical positional relation with a measurement subject according to a positional change of the movable member in the direction perpendicular to the two-dimensional plane when the surface of the movable body is located at each detection position, and a second sensor which detects the displacement of the movable member from a reference point.

48. A pattern forming apparatus that forms a pattern on an object, the apparatus comprising:

a patterning device which generates a pattern on the object; and

a movable body drive system according to claim 46, wherein

drive of a movable body on which the object is mounted is performed by the movable body drive system for pattern formation with respect to the object.

49. The pattern formation apparatus according to claim 48 wherein

the object has a sensitive layer, and the patterning device generates a pattern on the object by an exposure of the sensitive layer by irradiation of an energy beam.

50. An exposure apparatus that forms a pattern on an object by an irradiation of an energy beam, the apparatus comprising:

a patterning device that irradiates the energy beam on the object; and

a movable body drive system according to claim 46, wherein

the movable body drive system drives the movable body on which the object is mounted for relative movement of the energy beam and the object.