Method and apparatus which exposes a second object with a pattern formed on a first object and which performs statistical calculation based on position information of marks on the first object

• US 6,279,881 B1
• Filed: 02/24/2000
• Issued: 08/28/2001
• Est. Priority Date: 02/26/1993
• Status: Expired due to Term

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: Nishi, Kenji
• Primary Examiner(s): Allen, Stephone B.
• Application Number:
  US09/512,103
• Time in Patent Office: 551 Days
• Field of Search: 250/548, 355/43, 355/53, 355/55, 356/399-401
• US Class Current: 250/548
• CPC Class Codes: G03F 7/70358 Scanning exposure, i.e. relative movement of patterned beam and workpiece during imaging
• CPC Class Codes: G03F 7/70775 Position control, e.g. interferometers or encoders for determining the stage position
• 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 9/7088 Alignment mark detection, e.g. TTR, TTL, off-axis detection, array detector, video detection

Abstract

There is disclosed an exposure method for transferring, using an optical system for illuminating a mask having patterns to be transferred on a substrate and a projection optical system for projecting images of the patterns to the substrate, the patterns to the substrate through the projection optical system by means of scanning the mask and the substrate synchronously relative to the projection optical system. The method comprises the steps of providing a plurality of measuring marks on the mask formed along a relative scanning direction, and providing a plurality of reference marks formed on the stage corresponding to the measuring marks, respectively, moving the mask and the substrate synchronously in the relative scanning direction to measure successively a displacement amount between the measuring marks on the mask and the reference marks, and obtaining a correspondence relation between a coordinate system on the mask and a coordinate system on the stage according to the displacement amount.

Claims

1. A method for exposing a second object using a pattern of a first object, comprising:

detecting position information on a plurality of marks on said first object; and

obtaining a plurality of error parameters by performing a statistical calculation using one computer equation based on the detected position information.

2. A method according to claim 1, wherein said statistical calculation includes at least square approximation calculation.

3. A method according to claim 1, wherein said plurality of error parameters include linear error data.

4. A method according to claim 1, wherein said plurality of error parameters include error data of a first coordinate system for defining a position of said first object, with a second coordinate system for defining a position of said second object as a reference.

5. A method according to claim 1, wherein said plurality of error parameters include magnification error data.

6. A method according to claim 1, wherein said plurality of error parameters include rotation error data.

7. A method according to claim 1, wherein said plurality of error parameters include offset error data.

8. A method according to claim 1, further comprising:

moving said first object and said second object in respective predetermined scan directions during exposure of said second object.

9. A method according to claim 8, wherein said plurality of error parameters include scaling error data of a scan direction in a first coordinate system for defining a position of said first object and a scan direction in a second coordinate system for defining a position of said second object.

10. A method according to claim 8, wherein said plurality of error parameters include parallelism data of a scan direction in a first coordinate system for defining a position of said first object and a scan direction in a second coordinate system for defining a position of said second object.

11. A method according to claim 8, wherein said plurality of marks comprise a plurality of marks spaced apart from each other in a scan direction in a first coordinate system for defining a position of said first object.

12. A method of manufacturing a device including a process of exposing said second object with the pattern of said first object utilizing the method according to claim 1.

13. An exposure apparatus which exposes a second object with a pattern formed on a first object, comprising:

a mark detecting device, which includes a photoelectric sensor, and which detects position information on a plurality of marks on said first object based on outputs of the photoelectric sensor, and

a calculating device, which is electrically connected to said mark detecting device, which has one computer equation, and which obtains a plurality of error parameters by performing a statistical calculation using the computer equation based on the position information detected by the mark detecting device.

14. The apparatus according to claim 13, wherein said statistical calculation includes at least square approximation calculation.

15. The apparatus according to claim 13, wherein said plurality of error parameters include linear error data.

16. The apparatus according to claim 13, wherein said plurality of error parameters include error data of a first coordinate system for defining a position of said first object, with a second coordinate system for defining a position of said second object as a reference.

17. The apparatus according to claim 13, wherein said plurality of error parameters include magnification error data.

18. The apparatus according to claim 13, wherein said plurality of error parameters include rotation error data.

19. The apparatus according to claim 13, wherein said plurality of error parameters include offset error data.

20. The apparatus according to claim 13, wherein said exposure apparatus is a scanning exposure apparatus which moves said first object and said second object in respective predetermined scan directions during exposure of said second object.

21. The apparatus according to claim 20, wherein said plurality of error parameters include scaling error data of a scan direction in a first coordinate system for defining a position of said first object and a scan direction in a second coordinate system for defining a position of said second object.

22. The apparatus according to claim 20, wherein said plurality of error parameters include parallelism data of a scan direction in a first coordinate system for defining a position of said first object and a scan direction in a second coordinate system for defining a position of said second object.

23. The apparatus according to claim 20, wherein said plurality of marks comprise a plurality of marks spaced apart from each other in a scan direction in a first coordinate system for defining a position of said first object.