Exposure apparatus and an exposure method

• US 7,256,869 B2
• Filed: 12/29/2006
• Issued: 08/14/2007
• Est. Priority Date: 11/28/1996
• Status: Expired due to Fees

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: Nishi, Kenji
• Primary Examiner(s): NGUYEN, HUNG
• Application Number:
  US11/647,492
• Publication Number:
  US 20070109515A1
• Time in Patent Office: 228 Days
• Field of Search: 355/52, 355/53, 355/55, 355/67, 355/69, 355/72, 355/75, 355/77, 356399-401, 250/492.2, 250/548, 430/5, 430/30, 430/311, 430/322, 378/34
• US Class Current: 355/53
• CPC Class Codes: G03F 7/70216 Mask projection systems
• CPC Class Codes: G03F 7/70358 Scanning exposure, i.e. relative movement of patterned beam and workpiece during imaging
• CPC Class Codes: G03F 7/70425 Imaging strategies, e.g. for increasing throughput or resolution, printing product fields larger than the image field or compensating lithography- or non-lithography errors, e.g. proximity correction, mix-and-match, stitching or double patterning
• CPC Class Codes: G03F 7/70716 Stages
• CPC Class Codes: G03F 7/70733 Handling masks and workpieces, e.g. exchange of workpiece or mask, transport of workpiece or mask
• CPC Class Codes: G03F 9/70 for microlithography measuring printed patterns for monitoring overlay G03F7/70633 or focus G03F7/70641; projection system adjustment G03F7/70258; position control G03F7/70775
• CPC Class Codes: G03F 9/7003 Alignment type or strategy, e.g. leveling, global alignment
• CPC Class Codes: G03F 9/7015 Reference, i.e. alignment of original or workpiece with respect to a reference not on the original or workpiece
• CPC Class Codes: G03F 9/7026 Focusing
• CPC Class Codes: G03F 9/7088 Alignment mark detection, e.g. TTR, TTL, off-axis detection, array detector, video detection

Abstract

A scanning exposure apparatus includes a projection system, a stage system, a first detector and a control system. The stage system has first and second stages, each of which is movable independently in a plane while holding a substrate. The first detector detects focusing information of a vicinity of an outer circumference of the substrate during a detecting operation. The control system controls the stage system to perform the detecting operation with the first stage, while performing a first exposure operation on the substrate held by the second stage. After the first exposure operation, a second exposure operation for the substrate held on the first stage is performed, in which a shot area in the vicinity of the outer circumference of the substrate is exposed by moving the first stage while adjusting a position of the substrate surface held by the first stage using the detected focusing information.

Claims

1. An exposure apparatus which forms a pattern on an object, comprising:

a first holding member which holds an object;

a second holding member which holds an object;

a driving system which independently moves the first and second holding members in a two-dimensional plane;

an exposure portion, in which the first and second holding members are alternately provided so as to perform an exposure for the object held by each of the first and second holding members, including;

an exposure optical system of which a first portion is arranged in a first direction parallel to the two-dimensional plane and of which a second portion is arranged in a second direction perpendicular to the two-dimensional plane, and which irradiates onto the object an exposure beam from the first portion via the second portion; and

a first interferometer system which obtains positional information of one of the first and second holding members provided in the exposure portion;

a measurement portion, in which the first and second holding members are alternately provided so as to perform a measurement for the objects held by the first and second holding members, respectively, including a measurement system which is arranged apart from the second portion of the exposure optical system with respect to the first direction, and a second interferometer system which obtains positional information of the other of the first and second holding members provided in the measurement portion;

wherein each of the first and second holding members has a reflective surface used for the first and second interferometer systems; and

the other of the first and second holding members in the measurement portion is provided in the exposure portion in exchange for the one of the first and second holding members after the measurement of the object held by the other of the first and second holding members.

2. The apparatus according to claim 1, wherein one of the first and second holding members in the exposure portion is moved relative to the second portion of the exposure optical system for a scanning exposure of the object with the exposure beam.

3. The apparatus according to claim 2, wherein the exposure portion includes a mask holding member holding a mask illuminated with the exposure beam from the first portion of the exposure optical system, and a pattern image of the illuminated mask is projected on the object via the second portion of the exposure optical system.

4. The apparatus according to claim 3, wherein the mask includes a plurality of masks;

and the mask holding member holds the masks arranged in a direction along which the mask holding member is moved during the scanning exposure.

5. The apparatus according to claim 1, wherein the driving system includes a first movable member which is used commonly for the first and second holding members, and which moves the one holding member provided in the exposure portion;

and a second movable member which is used commonly for the first and second holding members, and which moves the other holding member provided in the measurement portion.

6. The apparatus according to claim 5, wherein the first and second holding members are moved on a common base by an electromagnetic force.

7. The apparatus according to claim 5, wherein the measurement by the measurement system includes a detection of alignment marks on the object.

8. The apparatus according to claim 7, wherein the measurement by the measurement system includes a detection of focusing information of the object.

9. The apparatus according to claim 5, further comprising:

a position control device which controls the first and second movable members, without using the first and second interferometer system, when the first and second holding members are detached from the first and second movable members, respectively.

10. The apparatus according to claim 9, wherein the position control device includes an encoder which detects positional information of the first and second movable members.

11. The apparatus according to claim 5, further comprising:

a switching device having coupling members which are respectively coupled to the first and second holding members to carry the first and second holding members between the first and second movable members.

12. The apparatus according to claim 1, wherein the driving system includes a first movable member which moves the first holding member in the exposure portion and the measurement portion, and a second movable member which moves the second holding member in the exposure portion and the measurement portion.

13. The apparatus according to claim 12, wherein the first and second movable members are moved by an electromagnetic force.

14. The apparatus according to claim 12, wherein the measurement includes a detection of alignment marks on the object by the measurement system.

15. The apparatus according to claim 14, wherein the measurement includes a detection of focusing information of the object by the measurement system.

16. The apparatus according to claim 12, wherein the measurement system includes first and second measuring devices which measure positional information of the objects held by the first and second holding member, respectively, and the second portion of the exposure optical system is disposed between the first and second measuring devices with respect to the first direction.

17. The apparatus according to claim 16, wherein the object held by the first holding member is disposed opposite to each of the first measuring device and the second portion of the exposure optical system by the first movable member;

and the object held by the second holding member is disposed opposite to each of the second measuring device and the second portion of the exposure optical system by the second movable member.

18. The apparatus according to claim 17, wherein the driving system independently moves the first and second movable members by a common actuator.

19. The apparatus according to claim 16, wherein the positional information measured by each of the first and second measuring devices includes at least one of positional information of alignment marks on the object and focusing information of the object.

20. A micro-device manufacturing method including a lithography process utilizing the exposure apparatus as defined in claim 1.

21. An exposure method of forming a pattern on an object, comprising:

providing a first holding member which holds an object in an exposure portion including an exposure optical system of which a first portion is arranged in a first direction parallel to a two-dimensional plane and a second portion is arranged in a second direction perpendicular to the two-dimensional plane, and a first interferometer system;

exposing the object with an exposure beam via the exposure optical system, while moving the first holding member on the two-dimensional plane by a driving system and measuring positional information of the first holding member by the first interferometer system;

providing a second holding member which holds an object in a measurement portion including a second interferometer system, and a measurement system arranged apart from the second portion of the exposure optical system with respect to the first direction;

measuring alignment information of the object by the measurement system, while moving the second holding member by the driving system and measuring positional information of the second holding member by the second interferometer system;

providing the second holding member in the exposure portion in exchange for the first holding member which holds the exposed object after the measurement of the alignment information; and

exposing the object held by the second holding member with the exposure beam via the exposure optical system based on the alignment information, while moving the second holding member on the two-dimensional plane by the driving system and measuring positional information of the second holding member by the first interferometer system;

wherein each of the first and second holding members has a reflective surface used for the first and second interferometer systems.

22. The method according to claim 21, wherein one of the first and second holding members provided in the exposure portion is moved relative to the second portion of the exposure optical system for a scanning exposure of the object with the exposure beam.

23. The method according to claim 22, wherein the exposure optical system illuminates a mask on a mask holding member with the exposure beam from the first portion, and projects a pattern image of the illuminated mask onto the object via the second portion.

24. The method according to claim 23, wherein the mask includes a plurality of masks;

and the mask holding member holds the masks arranged in a direction along which the mask holding member is moved during the scanning exposure.

25. The method according to claim 21, wherein one of the first and second holding members provided in the exposure portion is moved by a first movable member which is used commonly for the first and second holding members, and the other of the first and second holding members provided in the measurement portion is moved by a second movable member which is used commonly for the first and second holding members.

26. The method according to claim 25, wherein the first and second holding members are moved on a common base by an electromagnetic force.

27. The method according to claim 25, wherein the measurement by the measurement system includes a detection of alignment marks on the object.

28. The method according to claim 27, wherein the measurement by the measurement system includes a detection of focusing information of the object.

29. The method according to claim 25, wherein the first and second movable members are moved, without using the first and second interferometer system, when the first and second holding members are detached from the first and second movable members, respectively.

30. The method according to claim 29, wherein positional information of the first and second movable members is detected by an encoder when the first and second holding members are detached from the first and second movable members, respectively.

31. The method according to claim 25, wherein the first and second holding members are respectively coupled to coupling members of a switching device to carry the first and second holding members between the first and second movable members.

32. The method according to claim 21, wherein the first holding member is moved in the exposure portion and the measurement portion by a first movable member, and the second holding member is moved in the exposure portion and the measurement portion by a second movable member.

33. The method according to claim 32, wherein the first and second movable members are moved by an electromagnetic force.

34. The method according to claim 32, wherein the measurement by the measurement system includes a detection of alignment marks on the object.

35. The method according to claim 34, wherein the measurement by the measurement system includes a detection of focusing information of the object.

36. The method according to claim 32, wherein positional information of the objects held by the first and second holding member is measured by first and second measuring devices of the measurement system respectively, the second portion of the exposure optical system being disposed between the first and second measuring devices with respect to the first direction.

37. The method according to claim 36, wherein the object held by the first holding member is disposed opposite to each of the first measuring device and the second portion of the exposure optical system by the first movable member;

and the object held by the second holding member is disposed opposite to each of the second measuring device and the second portion of the exposure optical system by the second movable member.

38. The method according to claim 37, wherein the first and second movable members are independently moved by a common actuator.

39. The method according to claim 36, wherein the positional information measured by each of the first and second measuring devices includes at least one of positional information of alignment marks on the object and focusing information of the object.

40. A micro-device manufacturing method including a lithography process utilizing the exposure method as defined in claim 21.