Exposure apparatus and method for producing device

• US 7,834,976 B2
• Filed: 07/07/2006
• Issued: 11/16/2010
• Est. Priority Date: 12/10/2002
• Status: Active Grant

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: Nei, Masahiro, Kobayashi, Naoyuki
• Primary Examiner(s): Nguyen; Hung Henry
• Application Number:
  US11/482,153
• Publication Number:
  US 20060250596A1
• Time in Patent Office: 1,593 Days
• Field of Search: 355/30, 355/52, 355/53, 355/55, 355 67- 71, 250/548
• US Class Current: 355/53
• CPC Class Codes: G03F 7/70341 Details of immersion lithography aspects, e.g. exposure media or control of immersion liquid supply chemical composition of immersion liquids G03F7/2041
• CPC Class Codes: G03F 9/7011 Pre-exposure scan; original with original holder alignment; Prealignment, i.e. workpiece with workpiece holder
• 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 9/7019 Calibration
• CPC Class Codes: G03F 9/7034 Leveling
• CPC Class Codes: G03F 9/7046 Strategy, e.g. mark, sensor or wavelength selection
• CPC Class Codes: G03F 9/7088 Alignment mark detection, e.g. TTR, TTL, off-axis detection, array detector, video detection
• CPC Class Codes: G03F 9/7096 Arrangement, mounting, housing, environment, cleaning or maintenance of apparatus

Abstract

An exposure apparatus includes a projection optical system for projecting a pattern on a reticle onto an object to be exposed. The apparatus also includes a reference mark that serves as a reference for an alignment between the reticle and the object. The apparatus also includes a first fluid that has a refractive index of 1 or greater, and fills a space between at least part of said projection optical system and the object and a space between at least part of said projection optical system and the reference mark. In addition, an alignment mechanism aligns the object by using said projection optical system and the first fluid.

Claims

1. An exposure apparatus comprising:

a projection optical system that projects a pattern onto an object to be exposed through a liquid;

a reference mark that serves as a reference for an alignment between the pattern and the object, the reference mark being provided separate from the object; and

an alignment system that aligns the object with the pattern based on alignment information obtained when the liquid is disposed in a space between the projection optical system and the reference mark, wherein

the reference mark is part of a member that is located adjacent to the object, the member being positioned relative to the object so that the liquid in the space between the projection optical system and the reference mark is retained in contact with the projection optical system when the member and the object are moved to position the object opposite to the projection optical system such that the liquid fills a gap between the projection optical system and the object.

2. An exposure apparatus according to claim 1, further comprising:

a stage on which the object is mounted; and

wherein the member includes a reference plate mounted on the stage, and the reference mark is provided on the reference plate.

3. An exposure apparatus according to claim 1, wherein the alignment system includes a light-receiving element for receiving light.

4. An exposure apparatus according to claim 1, wherein the alignment system includes an irradiating section for irradiating light.

5. A device manufacturing method comprising:

exposing an object using an exposure apparatus according to claim 1; and

processing the object that has been exposed.

12. The apparatus according to claim 1, wherein the member has an edge that is sufficiently close to an edge of the object so that the liquid is retained in contact with the projection optical system when the object and the member are moved from a first state in which the reference mark is positioned opposite to the projection optical system to a second state in which the object is positioned opposite to the projection optical system.

6. An exposure apparatus comprising:

a projection optical system that projects a pattern onto an object to be exposed through a liquid;

a stage on which the object is mounted, the stage having a reference provided separate from the object;

a first alignment system by which an alignment mark of the object is detected; and

a second alignment system by which positional relation between the pattern and the reference is obtained by using the projection optical system when a space between the projection optical system and the reference is filled with the liquid, wherein

the reference is part of a member that is located adjacent to the object mounted on the stage, the member being positioned on the stage relative to the object mounted on the stage so that the liquid in the space between the projection optical system and the reference is retained in contact with the projection optical system when the stage is moved to position the object opposite to the projection optical system such that the liquid fills a gap between the projection optical system and the object.

7. The exposure apparatus according to claim 6, wherein based on information obtained by detecting the alignment mark of the object and the positional relation, the pattern and the object are aligned.

8. The apparatus according to claim 6, wherein positional relation between the alignment mark of the object and the reference is detected by using the first alignment system.

9. A device manufacturing method comprising:

exposing an object using an exposure apparatus according to claim 6; and

processing the object that has been exposed.

13. The apparatus according to claim 6, wherein the member has an edge that is sufficiently close to an edge of the object mounted on the stage so that the liquid is retained in contact with the projection optical system when the stage is moved from a first state in which the reference is positioned opposite to the projection optical system to a second state in which the object is positioned opposite to the projection optical system.

10. An exposure method that transfers an image of a pattern onto an object through a liquid using an exposure apparatus having a projection optical system and a reference mark that serves as a reference for an alignment between the pattern and the object, the reference mark being provided separate from the object, the method comprising:

projecting the pattern through the projection optical system and the liquid onto the object; and

aligning the object with the pattern based on alignment information obtained when the liquid is disposed in a space between the projection optical system and the reference mark, wherein

the reference mark is part of a member that is located adjacent to the object, the member being positioned relative to the object so that the liquid in the space between the projection optical system and the reference mark is retained in contact with the projection optical system when the member and the object are moved to position the object opposite to the projection optical system such that the liquid fills a gap between the projection optical system and the object.

11. The method according to claim 10, wherein the member has an edge that is sufficiently close to an edge of the object so that the liquid is retained in contact with the projection optical system when the object and the member are moved from a first state in which the reference mark is positioned opposite to the projection optical system to a second state in which the object is positioned opposite to the projection optical system.