Linear motor, moving stage system, exposure apparatus, and device manufacturing method

• US 7,348,695 B2
• Filed: 12/01/2005
• Issued: 03/25/2008
• Est. Priority Date: 02/13/2003
• Status: Active Grant

• Current Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Original Assignee: Canon Kabushiki Kaisha (Canon Inc.)
• Inventors: Asano, Toshiya, Korenaga, Nobushige
• Primary Examiner(s): Lam; Thanh
• Application Number:
  US11/290,498
• Publication Number:
  US 20060082225A1
• Time in Patent Office: 845 Days
• Field of Search: 310/12, 355/53
• US Class Current: 310/12.06
• CPC Class Codes: G03F 7/70758 Drive means, e.g. actuators, motors for long- or short-stroke modules or fine or coarse driving
• CPC Class Codes: H01J 2237/20221 Translation
• CPC Class Codes: H01J 2237/20278 Motorised movement
• CPC Class Codes: H01J 2237/3175 Lithography
• CPC Class Codes: H01J 37/20 Means for supporting or positioning the objects or the material; Means for adjusting diaphragms or lenses associated with the support introducing the objects H01J37/18
• CPC Class Codes: H02K 1/276 Magnets embedded in the magnetic core, e.g. interior permanent magnets [IPM]
• CPC Class Codes: H02K 41/031 of the permanent magnet type

Abstract

A linear motor includes a coil and a plurality of magnets disposed along a central axis of the coil. The magnetization directions of the plurality of magnets have different tilts with respect to the central axis.

Claims

1. In a linear motor having a coil and a magnet unit including a plurality of magnets which are disposed along a movement direction and which have magnetic poles disposed with a mutual difference of ninety degrees, the improvement comprising:

a plurality of magnets provided along a central axis of said coil, and including at least two magnets which are disposed so that tilts of their magnetized directions, with respect to the central axis, which are based on an error of magnetized direction, are placed in mutually opposite directions.

2. A linear motor according to claim 1, wherein said at least two magnets are disposed so that their magnetic pole directions are tilted inversely with respect to the central axis.

3. A linear motor according to claim 1, wherein said plurality of magnets provided along the central axis have their magnetic pole directions tilted with respect to the central axis, and wherein a sum of the tilts of the magnetic pole directions of said plurality of magnets along the central axis is equal to or approximately equal to zero.

4. A stage system, comprising:

a linear motor as recited in claim 1; and

a stage to be driven by said linear motor.

5. An exposure apparatus, comprising:

a stage system as recited in claim 4, configured to position at least one of an original and a substrate; and

exposure means configured to transfer an image of the original to the substrate.

6. A device manufacturing method, comprising the steps of:

preparing an exposure apparatus as recited in claim 5; and

producing a device by use of the exposure apparatus.

7. A linear motor, comprising:

a plurality of coils disposed along a movement direction of said linear motor; and

first and second magnet groups each having a plurality of magnets disposed along the movement direction,

wherein said first magnet group includes first magnets disposed at intervals of a magnetic pole pitch, and second magnets being sandwiched by adjacent first magnets,

wherein said second magnet group includes third magnets disposed at intervals of a magnetic pole pitch, and fourth magnets being sandwiched by adjacent third magnets,

wherein said first magnets and said third magnets are disposed in arrays parallel to a central axis of said coils, and

wherein said first magnets and said third magnets are disposed so that tilts of their magnetized directions, with respect to the central axis, which are based on an error of magnetized direction, are placed in mutually opposite directions.

8. A linear motor according to claim 7, wherein said first and third magnets have a designed magnetization direction which is parallel to the central axis of said coils.

9. A linear motor according to claim 7, wherein the magnetized directions of said first and third magnets are disposed to tilt so that a force produced between a coil and a first magnet in a direction other than the movement direction cancels a force produced between a coil and a third magnet in a direction other than the movement direction.

10. A linear motor according to claim 7, wherein said first magnets and said third magnets are so disposed that tilts of their magnetized directions with respect to a straight line parallel to the movement direction are opposite to each other.

11. A stage system, comprising:

a linear motor as recited in claim 7; and

a stage to be driven by said linear motor.

12. An exposure apparatus, comprising:

a stage system as recited in claim 11; and

exposure means configured to transfer an image of an original to a substrate.

13. A device manufacturing method, comprising the steps of:

preparing an exposure apparatus as recited in claim 12; and

producing a device by use of the exposure apparatus.