Platform positionable in at least three degrees of freedom by interaction with coils
AssigneeNikon Corporation
InventorsMark K. Takita, W. Thomas Novak, Andrew J. Hazelton
Life of this patent
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Abstract
The invention comprises a platform positionable in at least three degrees of freedom at least partly by interaction with coils. The platform includes a support member having a surface. Magnets are attached to the surface and part of a magnet bearing is attached to the support member. Inner and outer platforms are coupled to each other by magnet bearings and interact with coils to position the inner platform in six degrees of freedom. The invention may be particularly useful in precise positioning of semiconductor wafers and materials during photolithography and other processing.
Claims24
A positioning platform comprising:
- a member having a generally planar surface;
- a plurality of first magnets disposed on said member surface and having a plurality of first magnetic fields generally perpendicular to said member surface, the magnetic field of each magnet being directed in an opposite direction from the magnetic field of an adjacent magnet along at least one direction;
- and
- a first magnet bearing portion of each of at least one bearing, said first magnet bearing portion being attached to said member and comprising a magnetically permeable material.
A planar electric motor comprising:
- a first member defining an aperture therethrough;
- a second member disposed within said aperture and movable relative to said first member within said aperture;
- a plurality of first magnets disposed on a surface of one of said first and second members and having a plurality of first magnetic fields;
- a planar coil array positioned adjacent to the plurality of first magnets and operable to interact with the first magnet fields to provide a force between the coil array and the first magnets in a first and a second direction.
A lithography system comprising:
- an optical system for imaging a pattern onto an article, the optical system comprising a frame;
- a member defining an aperture therethrough;
- a stage disposed within said aperture for supporting the article relative to the optical system for imaging, said stage being movable relative to said member within said aperture;
- at least one bearing coupling said member to said stage and allowing movement of said member relative to said stage;
- a plurality of first magnets having a plurality of first magnetic fields and disposed on one of said member and stage;
- and
- a planar coil array positioned adjacent to the plurality of first magnets and operable to interact with the first magnet fields to provide a force between the coil array and the first magnets in a first and a second direction, said coil array being attached to the frame.
Dependencies are inferred from the claim text.