Movable body drive method and movable body drive system, pattern formation method and apparatus, exposure method and apparatus, device manufacturing method, and calibration method
A controller measures positional information of a stage within an XY plane using three encoders which at least include one each of an X encoder and a Y encoder of an encoder system, and the stage is driven in the XY plane, based on measurement results of the positional information and positional information (p 1 , q 1 ), (p 2 , q 2 ), and (p 3 , q 3 ) in a surface parallel to the XY plane of a head (an encoder) used for measurement of the positional information. Accordingly, it becomes possible to control the movement of the stage with good precision, while switching the head (the encoder) used for control during the movement of the stage using the encoder system which includes a plurality of heads.
1. An exposure method of exposing an object with an illumination light via a projection optical system and a liquid, the method comprising:
forming a liquid immersion area under the projection optical system with the liquid by a nozzle unit provided to surround an lower end part of the projection optical system;
placing the object to face an alignment system by a stage so that a mark of the object is detected by the alignment system, the stage being movable in at least a first direction and a second direction orthogonal to each other within a predetermined plane perpendicular to an optical axis of the projection optical system and having a holder to hold the object, and the alignment system being arranged away from the projection optical system;
placing the object to face the projection optical system by the stage so that the object is exposed with the illumination light via the projection optical system and the liquid of the liquid immersion area;
in an encoder system having one of a grating section and a head provided at the stage and the other of the grating section and the head provided on an outer side of the nozzle unit with respect to the projection optical system, by a plurality of the heads that face the grating section, measuring positional information of the stage; and
controlling a movement of the stage while compensating for a measurement error of the encoder system that occurs due to the head, based on measurement information of the encoder system, wherein
in each of a detection operation of the mark and an exposure operation of the object, the positional information of the stage is measured by the encoder system.
2. The exposure method according to claim 1 , wherein
one of the plurality of heads is switched to another head by a movement of the stage, and the positional information to be measured by the another head to be used after the switching is decided based on the positional information measured by the plurality of heads used before the switching.
3. The exposure method according to claim 2 , wherein
after the switching, the positional information of the stage is measured by a plurality of the heads including the another head, and measurement by the another head is performed using the positional information that has been decided.
4. The exposure method according to claim 3 , wherein
the positional information to be measured by the another head is decided while a head used before the switching and a head to be used after the switching both face the grating section.
5. The exposure method according to claim 3 , wherein
the switching is performed while a head used before the switching and a head to be used after the switching both face the grating section.
6. The exposure method according to claim 3 , wherein
decision of the positional information to be measured by the another head is made and the switching is performed, while the plurality of heads used before the switching and the another head both face the grating section.
7. The exposure method according to claim 3 , wherein
before and after the switching each, three or four of the heads face the grating section, and
during a movement of the stage, the number of the heads that face the grating section is changed from one of three and four to the other.
8. The exposure method according to claim 3 , wherein
the positional information to be measured by the another head is decided so that a position of the stage is maintained or the positional information of the stage continuously links before and the after the switching.
9. The exposure method according to claim 3 , wherein
in the decision of the positional information to be measured by the another head, positional information of the stage in a direction different from the first and the second directions is used.
10. The exposure method according to claim 9 , wherein
the direction different from the first and the second directions includes a rotational direction within the predetermined plane.
11. The exposure method according to claim 3 , wherein
in a movement of the stage, at least one of a measurement error of the encoder system related to the first and the second directions that occurs due to a displacement of the stage in a direction different from the first and the second directions and a measurement error of the encoder system that occurs due to inclination of the stage with respect to the predetermined plane is also compensated for.
12. The exposure method according to claim 11 , wherein
the direction different from the first and the second directions includes at least one of a direction orthogonal to the predetermined plane, a rotational direction around an axis orthogonal to the predetermined plane and a rotational direction around an axis parallel to the predetermined plane.
13. The exposure method according to claim 11 , wherein
in a movement of the stage, a measurement error of the encoder system that occurs due to at least one of flatness and a formation error of the grating section or at least one of a displacement and an optical property of the head is compensated for.
14. The exposure method according to claim 3 , wherein
the heads are provided at the stage, and the stage is moved under the grating section in the exposure.
15. The exposure method according to claim 3 , wherein
before the switching the positional information of the stage is measured by three of the heads, and by a movement of the stage, the three of the heads are switched to three heads including the another head that is different from the three of the heads used before the switching, and
the positional information to be measured by the another head is decided based on the positional information measured by the three of the heads used before the switching.
16. The exposure method according to claim 15 , wherein
the positional information to be measured by the another head is decided while four heads including the three of the heads used before the switching and the another head face the grating section.
17. The exposure method according to claim 16 , wherein
the switching is performed while the four heads face the grating section.
18. The exposure method according to claim 17 , wherein
the grating section includes four scale members each having a reflection-type grating formed, and
the positional information of the stage is measured by three or four heads that are placed facing three or four of the four scale members, respectively.
19. The exposure method according to claim 18 , wherein
by a movement of the stage, one of the three heads and the four heads is changed to the other.
20. A device manufacturing method, including
exposing a substrate using the exposure method according to claim 1 ; and
developing the substrate that has been exposed.
21. An exposure apparatus that exposes an object with an illumination light via a projection optical system and a liquid, the apparatus comprising:
a local liquid immersion device that has a nozzle unit provided to surround an lower end part of the projection optical system and forms a liquid immersion area under the projection optical system with the liquid;
a stage that has a holder to hold the object and is movable in at least a first direction and a second direction orthogonal to each other within a predetermined plane perpendicular to an optical axis of the projection optical system;
a drive system having a motor that drives the stage;
an alignment system arranged away from the projection optical system, that detects a mark of the object;
an encoder system having one of a grating section and a head provided at the stage and the other of the grating section and the head provided on an outer side of the nozzle unit with respect to the projection optical system, the encoder system measuring positional information of the stage by a plurality of the heads that face the grating section; and
a controller coupled to the drive system, the controller controlling a movement of the stage while compensating for a measurement error of the encoder system that occurs due to the head, based on measurement information of the encoder system, wherein
in each of a detection operation of the mark and an exposure operation of the object, the positional information of the stage is measured by the encoder system.
22. The exposure apparatus according to claim 21 , wherein
one of the plurality of heads is switched to another head by a movement of the stage, and the positional information to be measured by the another head to be used after the switching is decided based on the positional information measured by the plurality of heads used before the switching.
23. The exposure apparatus according to claim 22 , wherein
after the switching, the positional information of the stage is measured by a plurality of the heads including the another head, and measurement by the another head is performed using the positional information that has been decided.
24. The exposure apparatus according to claim 23 , wherein
the positional information to be measured by the another head is decided while a head used before the switching and a head to be used after the switching both face the grating section.
25. The exposure apparatus according to claim 23 , wherein
the switching is performed while a head used before the switching and a head to be used after the switching both face the grating section.
26. The exposure apparatus according to claim 23 , wherein
decision of the positional information to be measured by the another head is made and the switching is performed, while the plurality of heads used before the switching and the another head both face the grating section.
27. The exposure apparatus according to claim 23 , wherein
before and after the switching each, three or four of the heads face the grating section, and
during a movement of the stage, the number of the heads that face the grating section is changed from one of three and four to the other.
28. The exposure apparatus according to claim 23 , wherein
the positional information to be measured by the another head is decided so that a position of the stage is maintained or the positional information of the stage continuously links before and the after the switching.
29. The exposure apparatus according to claim 23 , wherein
in the decision of the positional information to be measured by the another head, positional information of the stage in a direction different from the first and the second directions is used.
30. The exposure apparatus according to claim 29 , wherein
the direction different from the first and the second directions includes a rotational direction within the predetermined plane.
31. The exposure apparatus according to claim 23 , wherein
the controller controls a movement of the stage, while also compensating for at least one of a measurement error of the encoder system related to the first and the second directions that occurs due to a displacement of the stage in a direction different from the first and the second directions and a measurement error of the encoder system that occurs due to inclination of the stage with respect to the predetermined plane.
32. The exposure apparatus according to claim 31 , wherein
the direction different from the first and the second directions includes at least one of a direction orthogonal to the predetermined plane, a rotational direction around an axis orthogonal to the predetermined plane and a rotational direction around an axis parallel to the predetermined plane.
33. The exposure apparatus according to claim 31 , wherein
the controller controls a movement of the stage, while compensating for a measurement error of the encoder system that occurs due to at least one of flatness and a formation error of the grating section or at least one of a displacement and an optical property of the head.
34. The exposure apparatus according to claim 23 , wherein
the heads are provided at the stage, and the stage is moved under the grating section in the exposure.
35. The exposure apparatus according to claim 23 , wherein
before the switching the positional information of the stage is measured by three of the heads, and by a movement of the stage, the three of the heads are switched to three heads including the another head that is different from the three of the heads used before the switching, and
the positional information to be measured by the another head is decided based on the positional information measured by the three of the heads used before the switching.
36. The exposure apparatus according to claim 35 , wherein
the positional information to be measured by the another head is decided while four heads including the three of the heads used before the switching and the another head face the grating section.
37. The exposure apparatus according to claim 36 , wherein
the switching is performed while the four heads face the grating section.
38. The exposure apparatus according to claim 37 , wherein
the grating section includes four scale members each having a reflection-type grating formed, and
the positional information of the stage is measured by three or four heads that are placed facing three or four of the four scale members, respectively.
39. The exposure apparatus according to claim 38 , wherein
by a movement of the stage, one of the three heads and the four heads is changed to the other.
40. A device manufacturing method, including
exposing a substrate using the exposure apparatus according to claim 21 ; and
developing the substrate that has been exposed.
41. A method of making an exposure apparatus that exposes an object with an illumination light via a projection optical system and a liquid, the method comprising:
providing a local liquid immersion device that has a nozzle unit provided to surround an lower end part of the projection optical system and forms a liquid immersion area under the projection optical system with the liquid;
providing a stage that has a holder to hold the object and is movable in at least a first direction and a second direction orthogonal to each other within a predetermined plane perpendicular to an optical axis of the projection optical system;
providing a drive system having a motor that drives the stage;
providing an alignment system arranged away from the projection optical system, that detects a mark of the object;
providing an encoder system having one of a grating section and a head provided at the stage and the other of the grating section and the head provided on an outer side of the nozzle unit with respect to the projection optical system, the encoder system measuring positional information of the stage by a plurality of the heads that face the grating section; and
coupling a controller to the drive system, the controller controlling a movement of the stage while compensating for a measurement error of the encoder system that occurs due to the head, based on measurement information of the encoder system, wherein
in each of a detection operation of the mark and an exposure operation of the object, the positional information of the stage is measured by the encoder system.