Measuring apparatus and method, processing apparatus and method, pattern forming apparatus and method, exposure apparatus and method, and device manufacturing method

• US 8,027,021 B2
• Filed: 02/21/2007
• Issued: 09/27/2011
• Est. Priority Date: 02/21/2006
• Status: Expired due to Fees

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: Shibazaki, Yuichi
• Primary Examiner(s): Glick; Edward J
• Assistant Examiner(s): Persaud; Deoram
• Application Number:
  US11/708,601
• Publication Number:
  US 20080043212A1
• Time in Patent Office: 1,679 Days
• Field of Search: 356/498, 356/499, 356/500, 356/614, 355/53, 355/72, 355/77
• US Class Current: 355/53
• CPC Class Codes: G01D 2205/90 Two-dimensional encoders, i.e. having one or two codes extending in two directions
• CPC Class Codes: G01D 2205/95 Three-dimensional encoders, i.e. having codes extending in three directions
• CPC Class Codes: G01D 5/38 by diffraction gratings
• CPC Class Codes: G03F 7/70191 Optical correction elements, filters or phase plates for controlling intensity, wavelength, polarisation, phase or the like
• 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 7/70666 Aerial image, i.e. measuring the image of the patterned exposure light at the image plane of the projection system
• CPC Class Codes: G03F 7/70775 Position control, e.g. interferometers or encoders for determining the stage position
• CPC Class Codes: G03F 9/7026 Focusing

Abstract

Position information of a movable body within an XY plane is measured with high accuracy by an encoder system whose measurement values have favorable short-term stability, without being affected by air fluctuations, and also position information of the movable body in a Z-axis direction orthogonal to the XY plane is measured with high accuracy by a surface position measuring system, without being affected by air fluctuations. In this case, since both of the encoder system and the surface position measuring system directly measure the upper surface of the movable body, simple and direct position control of the movable body can be performed.

Claims

1. A measuring apparatus that measures position information of a movable body that moves within a predetermined plane, the apparatus comprising:

an encoder system that includes a plurality of scale members arranged on the movable body and each having a grating formed thereon and a plurality of heads that each irradiate a light to each of the plurality of scale members and individually receive a reflected light from each of the gratings, and measures position information of the movable body within the plane; and

a surface position measuring system that includes a plurality of surface position sensors that, by each irradiating a light to the plurality of scale members from a direction orthogonal to the plane and receiving the reflected light, measure position information of the scale members in the direction orthogonal to the plane at an irradiation point of the light, and measures position information of the movable body in the direction orthogonal to the plane and in a tilt direction with respect to the plane.

2. The measuring apparatus of claim 1, wherein

the plurality of scale members include a first scale member that has a first grating formed thereon and having a periodic direction in a predetermined direction within the plane,

the plurality of heads include a plurality of first heads which each constitute a first encoder that measures position information of the movable body by irradiating a detection light to the first scale member, and which are placed at a predetermined distance along a first direction parallel to the plane, and

some of the plurality of the surface position sensors are placed at a predetermined distance in the first direction.

3. The measuring apparatus of claim 2, wherein

the first grating has a periodic direction in one direction within the plane,

the plurality of scale members further include a second scale member that has a second grating formed thereon and having a periodic direction in a direction intersecting the periodic direction of the first grating, and

the plurality of heads further include a plurality of second heads which each constitute a second encoder that measures position information of the movable body by irradiating a detection light to the second scale member, and which are placed at a predetermined distance along a second direction orthogonal to the first direction within the plane.

4. The measuring apparatus of claim 2, wherein

the some of the surface position sensors and the plurality of first heads are alternately placed in the first direction.

5. The measuring apparatus of claim 4, wherein

the some of the surface position sensors and the plurality of first heads are placed on a same straight line in the first direction.

6. The measuring apparatus of claim 2, further comprising:

a surface position detecting unit that has a plurality of detection points that are set at a predetermined distance parallel to an array of the plurality of first heads along a straight line in the first direction, and detects surface position information of a surface of a target object at the plurality of detection points set on the target object by irradiating a detection beam to each of the plurality of detection points and individually receiving a reflected light of the detection beam from the target object, wherein

in a vicinity of each of two detection points located near both end portions among the plurality of detection points of the surface position detecting unit, at least one of the surface position sensors is placed in a placement that corresponds to a placement of the some of the surface position sensors on a straight line in a second direction orthogonal to the first direction.

7. The measuring apparatus of claim 6, further comprising:

a controller that makes the surface position sensor that is placed in the vicinity of each of two detection points located near both end portions among the plurality of detection points and the surface position detecting unit be in a state of a simultaneous operation, and converts detection results at the plurality of detection points by the surface position detecting unit that have been obtained by the simultaneous operation into data assuming measurement results of the surface position sensors that have been obtained by the simultaneous operation as a datum.

8. The measuring apparatus of claim 6, further comprising:

an arithmetic processing unit that makes the surface position detecting unit irradiate the detection beam to a reference member that comprises a predetermined reference plane, and obtains a relation among measurement values of the plurality of detection points of the surface position detecting unit based on an output of the surface position detecting unit that has received a reflected light from the reference plane.

9. The measuring apparatus of claim 8, wherein

the reference member is kinematically supported on another movable body that moves independently from the movable body within the plane.

10. The measuring apparatus of claim 2, wherein

the plurality of surface position sensors are placed at a predetermined distance so as to correspond to each other on two straight lines that are located on one side and the other side with a straight line in the first direction connecting the plurality of first heads in between and are parallel to the straight line.

11. The measuring apparatus of claim 10, wherein

the plurality of surface position sensors are symmetrically placed with respect to the straight line in the first direction connecting the plurality of first heads.

12. The measuring apparatus of claim 10, wherein

the plurality of surface position sensors and the plurality of first heads are alternately placed in the first direction.

13. The measuring apparatus of claim 10, wherein

on each of one side and the other side of a second direction orthogonal to the first direction with each of the plurality of first heads in between, one of the surface position sensors is placed.

14. The measuring apparatus of claim 10, further comprising:

a surface position detecting unit that has a plurality of detection points that are set at a predetermined distance parallel to an array of the plurality of first heads along a straight line in the first direction, and detects surface position information of a surface of a target object at the plurality of detection points set on the target object by irradiating a detection beam to each of the plurality of detection points and individually receiving a reflected light of the detection beam from the target object, wherein

in a vicinity of each of two detection points located near both end portions among the plurality of detection points of the surface position detecting unit, at least one of the surface position sensors is placed in a placement that corresponds to a placement of the some of the surface position sensors on a straight line in a second direction orthogonal to the first direction.

15. The measuring apparatus of claim 14, further comprising:

a controller that makes the surface position sensor that is placed in the vicinity of each of two detection points located near both end portions among the plurality of detection points and the surface position detecting unit be in a state of a simultaneous operation, and converts detection results at the plurality of detection points by the surface position detecting unit that have been obtained by the simultaneous operation into data assuming measurement results of the surface position sensors that have been obtained by the simultaneous operation as a datum.

16. The measuring apparatus of claim 14, further comprising:

an arithmetic processing unit that makes the surface position detecting unit irradiate the detection beam to a reference member that comprises a predetermined reference plane, and obtains a relation among measurement values of the plurality of detection points of the surface position detecting unit based on an output of the surface position detecting unit that has received a reflected light from the reference plane.

17. The measuring apparatus of claim 16, wherein

the reference member is kinematically supported on another movable body that moves independently from the movable body within the plane.

18. The measuring apparatus of claim 2, further comprising:

a surface position detecting unit that has a plurality of detection points that are set at a predetermined distance parallel to an array of the plurality of first heads along a straight line in the first direction, and detects surface position information of a surface of a target object at the plurality of detection points set on the target object by irradiating a detection beam to each of the plurality of detection points and individually receiving a reflected light of the detection beam from the target object.

19. The measuring apparatus of claim 18, wherein

in the vicinity of each of two detections points located near both end portions among the plurality of detection points of the surface position detecting unit, at least one of the surface position sensors is placed.

20. The measuring apparatus of claim 19, wherein

on each of one side and the other side of a second direction orthogonal to the first direction with each of the two detection points in between, one of the surface position sensors is placed.

21. The measuring apparatus of claim 18, further comprising:

an arithmetic processing unit that makes the surface position detecting unit irradiate the detection beam to a reference member that comprises a predetermined reference plane, and obtains a relation among measurement values of the plurality of detection points of the surface position detecting unit based on an output of the surface position detecting unit that has received a reflected light from the reference plane.

22. The measuring apparatus of claim 21, wherein

the reference member is kinematically supported on another movable body that moves independently from the movable body within the plane.

23. The measuring apparatus of claim 1, wherein

the surface position measuring system performs transfer of measurement values between the plurality of surface position sensors according to movement of the movable body.

24. The measuring apparatus of claim 1, wherein

the surface position sensor is a sensor by a CD pickup method.

25. The measuring apparatus of claim 1, wherein

a pair of the scale members are arranged apart in the first direction on the movable body, and

the surface position measuring system further includes a computing unit that computes position information of the movable body in the direction orthogonal to the plane and tilt information of the movable body in the first direction based on measurement values of two of the surface position sensors that face the pair of the scale members respectively.

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

the measuring apparatus of claim 1 in which an object is mounted on the movable body; and

a pattern generating unit that generates the pattern.

27. The pattern forming apparatus of claim 26, wherein

the pattern generating unit irradiates an energy beam to the object.

28. A processing apparatus that performs a predetermined processing to an object mounted on a movable body that moves within a predetermined plane, the apparatus comprising:

a surface position measuring system that includes a plurality of surface position sensors that, by irradiating a light to the movable body from a direction orthogonal to the plane and receiving the reflected light, measure position information of a surface of the movable body in the direction orthogonal to the plane at an irradiation point of the light, and measures position information of the movable body in the direction orthogonal to the plane and in a tilt direction with respect to the plane;

a surface position detecting unit that detects surface position information of a surface of the object at a plurality of detection points by irradiating a detection beam to the object mounted on the movable body and receiving a reflected light of the detection beam; and

a controller that makes the surface position measuring system and the surface position detecting unit be in a state of a simultaneous operation, and converts detection results at the plurality of detection points by the surface position detecting unit that have been obtained by the simultaneous operation into data assuming measurement results of the surface position measuring system that have been obtained by the simultaneous operation as a datum.

29. The processing apparatus of claim 28, wherein

the plurality of surface position sensors included in the surface position measuring system are placed along a predetermined direction within the plane,

the plurality of detection points of the surface position detecting unit are arrayed parallel to the plurality of surface position sensors along the predetermined direction, and

the controller makes the surface position measuring system and the surface position detecting unit perform the simultaneous operation while the movable body that mounts the object is moving along a direction intersecting the predetermined direction.

30. The processing apparatus of claim 29, wherein

the plurality of surface position sensors include surface position sensors for mapping, at least one of the surface position sensors for mapping being placed in the vicinity of each of two detection points located near both end portions among the plurality of detection points of the surface position detecting unit, and

the controller converts a detection value at each detection point of the surface position detecting unit into data assuming a reference surface position, which has been obtained based on a measurement result of each of the surface position sensors for mapping, as a datum.

31. The processing apparatus of claim 30, wherein

the controller obtains information on position variation of the movable body in the direction orthogonal to the plane that occurs when the movable body moves in the predetermined direction, based on results that have been sequentially detected at the plurality of detection points of the surface position detecting unit, while moving the movable body on which the object is mounted in the predetermined direction.

32. The processing apparatus of claim 29, wherein

in a process in which the movable body moves from a place where the object is mounted on the movable body to a place where a processing of irradiating an energy beam to the object is performed, the controller performs the simultaneous operation and the conversion processing.

33. The processing apparatus of claim 32, wherein

the controller obtains information on position variation of the movable body in the direction orthogonal to the plane that occurs when the movable body moves in the predetermined direction, based on results that have been sequentially detected at the plurality of detection points of the surface position detecting unit, while moving the movable body on which the object is mounted in the predetermined direction.

34. The processing apparatus of claim 28, further comprising:

a mark detecting unit that detects a plurality of marks to be detected formed on the object, wherein

in a process from when a detection operation of the plurality of marks to be detected by the mark detecting unit is started until when the detection operation of the plurality of marks is completed, the controller starts a simultaneous operation of the surface position measuring system and the surface position detecting unit and also starts the conversion processing of the data.

35. The processing apparatus of claim 28, further comprising:

a reference member that comprises a reference plane parallel to the plane; and

an arithmetic processing unit that makes the surface position detecting unit irradiate the detection beam to the reference member, and based on an output of the surface position detecting unit that has received a reflection light from the reference plane, obtains a relation among measurement values of the plurality of detection points of the surface position detecting unit.

36. The processing apparatus of claim 35, wherein

the reference member is kinematically supported on another movable body that moves independently from the movable body within the plane.

37. The processing apparatus of claim 28, wherein

the surface position measuring system performs transfer of measurement values between the plurality of surface position sensors according to movement of the movable body.

38. The processing apparatus of claim 28, wherein

the surface position sensor is a sensor by a CD pickup method.

39. A pattern forming apparatus that forms a pattern on a target object, the apparatus comprising:

the processing apparatus of claim 28 in which the target object is mounted on the movable body; and

a pattern generating unit that generates the pattern.

40. The pattern forming apparatus of claim 39, wherein

the pattern generating unit irradiates an energy beam to the object.

41. A measuring method in which position information of a movable body that moves within a predetermined plane is measured, the method comprising:

a first process of measuring position information of the movable body within the plane, using an encoder system that includes a plurality of scale members arranged on the movable body and each having a grating formed thereon, and a plurality of heads that each irradiate a light to each of the plurality of scale members and individually receive a reflected light from each of the gratings; and

a second process of measuring position information of the movable body in a direction orthogonal to the plane and in a tilt direction with respect to the plane, using a surface position measuring system that includes a plurality of surface position sensors that, by each irradiating a light to the plurality of scale members from the direction orthogonal to the plane and receiving the reflected light, measure position information of the scale members in the direction orthogonal to the plane at an irradiation point of the light.

42. The measuring method of claim 41, wherein

in the second process, transfer of measurement values is performed between the plurality of surface position sensors of the surface position measuring system according to movement of the movable body.

43. A pattern forming method, comprising:

a process of measuring position information of the movable body in a state where an object is mounted on the movable body, using the measuring method of claim 41; and

a process of forming a pattern on the object by irradiating an energy beam.

44. A device manufacturing method, comprising:

a process of forming a pattern on an object by the pattern forming method of claim 43; and

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

45. A processing method in which a predetermined processing is performed to an object mounted on a movable body that moves within a predetermined plane, the method comprising:

a first process of making a surface position measuring system and a surface position detecting unit be in a state of a simultaneous operation, the surface position measuring system including a plurality of surface position sensors that, by irradiating a light to the movable body from a direction orthogonal to the plane and receiving the reflected light, measure position information of a surface of the movable body in the direction orthogonal to the plane at an irradiation point of the light, and measuring position information of the movable body in the direction orthogonal to the plane and in a tilt direction with respect to the plane, and the surface position detecting unit detecting surface position information of a surface of the object at a plurality of detection points by irradiating a detection beam to the object mounted on the movable body and receiving a reflected light of the detection beam; and

a second process of converting detection results at the plurality of detection points by the surface position detecting unit that have been obtained by the simultaneous operation in the first process into data assuming measurement results of the surface position measuring system that have been obtained by the simultaneous operation as a datum.

46. The processing method of claim 45, wherein

the plurality of surface position sensors included in the surface position measuring system are placed along a predetermined direction within the plane,

the plurality of detection points of the surface position detecting unit are arrayed parallel to the plurality of surface position sensors along the predetermined direction, and

the processing in the first process is performed while the movable body that mounts the object is moving along the direction orthogonal to the predetermined direction.

47. The processing method of claim 46, wherein

the plurality of surface position sensors include surface position sensors for mapping, at least one of the surface position sensors for mapping being placed in the vicinity of each of two detection points located near both end portions among the plurality of detection points of the surface position detecting unit, and

in the second process, a detection value at each detection point of the surface position detecting unit is converted into data assuming a reference surface position, which has been obtained based on a measurement result of each of the surface position sensors for mapping, as a datum.

48. The processing method of claim 47, further comprising:

a third process of obtaining information on position variation of the movable body in the direction orthogonal to the plane that occurs when the movable body moves in the predetermined direction, based on results that have been sequentially detected at the plurality of detection points of the surface position detecting unit, while moving the movable body on which the object is mounted in the predetermined direction.

49. The processing method of claim 46, wherein

in the process in which the movable body moves from a place where the object is mounted on the movable body to a place where the predetermined processing is performed to the object, the processings in the first and second processes are performed.

50. The processing method of claim 49, further comprising:

a third process of obtaining information on position variation of the movable body in the direction orthogonal to the plane that occurs when the movable body moves in the predetermined direction, based on results that have been sequentially detected at the plurality of detection points of the surface position detecting unit, while moving the movable body on which the object is mounted in the predetermined direction.

51. The processing method of claim 45, wherein

in the process from when an operation of detecting a plurality of marks to be detected formed on the object by a mark detecting unit is started until when the operation is completed, the processings in the first and second processes are both started.

52. The processing method of claim 45, wherein

the predetermined processing includes a processing of forming a pattern on the object.

53. The processing method of claim 52, wherein

the pattern is formed on the object by irradiating an energy beam.

54. A device manufacturing method, comprising:

a process of forming a pattern on an object by the processing method of claim 52; and

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