Substrate placement in immersion lithography

• US 10,345,711 B2
• Filed: 08/21/2017
• Issued: 07/09/2019
• Est. Priority Date: 12/10/2004
• Status: Active Grant

• Current Assignee: ASML Netherlands BV (ASML Holding NV)
• Original Assignee: ASML Netherlands BV (ASML Holding NV)
• Inventors: Hoogendam, Christiaan Alexander, Nijmeijer, Gerrit Johannes, Cuperus, Minne, Van Eijck, Petrus Anton Willem Cornelia Maria
• Primary Examiner(s): Nguyen, Hung
• Application Number:
  US15/682,135
• Publication Number:
  US 20180067401A1
• Time in Patent Office: 687 Days
• Field of Search: 355 30, 355 53
• CPC Class Codes: G01B 11/14 for measuring distance or clearance between spaced objects or spaced apertures G01B11/26 takes precedence; rangefinders G01C3/00
• CPC Class Codes: G01B 11/26 for measuring angles or tapers; for testing the alignment of axes
• CPC Class Codes: G01B 11/272 using photoelectric detection means
• 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 7/707 Chucks, e.g. chucking or un-chucking operations or structural details
• CPC Class Codes: G03F 7/70716 Stages
• CPC Class Codes: G03F 7/70775 Position control, e.g. interferometers or encoders for determining the stage position
• CPC Class Codes: G03F 9/7011 Pre-exposure scan; original with original holder alignment; Prealignment, i.e. workpiece with workpiece holder

Abstract

A method for determining an offset between a center of a substrate and a center of a depression in a chuck includes providing a test substrate to the depression, the test substrate having a dimension smaller than a dimension of the depression, measuring a position of an alignment mark of the test substrate while in the depression, and determining the offset between the center of the substrate and the center of the depression from the position of the alignment mark.

Claims

1. An exposure apparatus configured to expose an object with an exposure beam via a projection optical system and a liquid, the apparatus comprising:

a local liquid immersion member configured to form a liquid immersion area with a liquid under the projection optical system;

a first stage that has an upper surface contactable with the liquid immersion area and a holder disposed in a depressed section of the upper surface, the first stage being capable of holding the object with the holder in the depressed section so that a gap is formed between a surface of the object and the upper surface;

a second stage;

a detection device comprising a detector;

a drive system configured to drive at least the first stage, the drive system configured to drive the first stage so that the object held in the depressed section is moved relative to the liquid immersion area that is formed between the projection optical system and a part of the object and so that the immersion liquid reaches the gap; and

a control system configured to control driving of at least the first stage, wherein the control system is configured to control driving of at least the first stage based on periphery positional information of at least the first stage obtained by the detector located above the first stage while obtaining the periphery positional information of the first stage.

2. The exposure apparatus according to claim 1, wherein while the liquid immersion area is maintained with the first stage that is placed facing the projection optical system, the second stage is located with a measurement device to take measurements using a surface on the second stage.

3. The exposure apparatus according to claim 1, wherein the first stage is capable of maintaining, with the upper surface, at least a part of the liquid immersion area that moves off from a surface of the object held in the depressed section.

4. The exposure apparatus according to claim 3, wherein the first stage holds the object in the depressed section so that the surface of the object is flush with the upper surface.

5. The exposure apparatus according to claim 4, further comprising:

a position measurement system that measures positional information of at least the first stage,

wherein the control system controls the driving of at least the first stage while measuring the positional information of at least the first stage with the position measurement system.

6. The exposure apparatus according to claim 5, further comprising:

a carrier system that has a pre-alignment device of the object, and carries the object, to which pre-alignment has been performed by the pre-alignment device, to above the first stage that is placed at an exchange position of the object, the exchange position being away from the projection optical system,

wherein the control system controls the first stage and/or the carrier system based on positional information of the depressed section, in order to load the object onto the first stage so that the object that is carried to above the first stage by the carrier system is placed in the depressed section.

7. The exposure apparatus according to claim 6, wherein the control system sets a positional relationship between the object to be loaded and the first stage based on the positional information of the depressed section so that the object is loaded without coming into contact with the upper surface of the first stage.

8. The exposure apparatus according to claim 7, wherein the object is held in the depressed section so that the gap is substantially even.

9. The exposure apparatus according to claim 6, wherein the positional information of the depressed section includes information on a center position or a shape of the depressed section.

19. A device manufacturing method, including:

a lithography process that uses the exposure apparatus according to claim 1; and

a device formation process.

10. An exposure method of exposing an object with an exposure beam via a projection optical system and a liquid, the method comprising:

supplying the liquid via a local liquid immersion member provided on a lower end side of the projection optical system, in order to form a liquid immersion area with the liquid under the projection optical system;

below a detector of a detection device, moving a first stage that has an upper surface contactable with the liquid immersion area and a holder disposed in a depressed section of the upper surface and that is capable of holding the object with the holder in the depressed section so that a gap is formed between a surface of the object and the upper surface, so that the object held in the depressed section is moved relative to the liquid immersion area that is formed between the projection optical system and a part of the object and also the immersion liquid reaches the gap;

moving the first stage, wherein moving of at least the first stage is controlled based on periphery positional information of at least the first stage obtained by the detector located above the first stage while obtaining the periphery positional information of the first stage; and

using a second stage for taking measurements.

11. The exposure method according to claim 10, wherein while the liquid immersion area is maintained with the first stage that is placed facing the projection optical system, the second stage is located with a measurement device to take measurements using a surface on the second stage.

12. The exposure method according to claim 11, wherein while moving the first stage that is placed facing the projection optical system so that the object is moved relative to the liquid immersion area, at least a part of the liquid immersion area that moves off from a surface of the object is maintained with the upper surface of the first stage.

13. The exposure method according to claim 12, wherein the object is held in the depressed section so that the surface of the object is flush with the upper surface of the first stage.

14. The exposure method according to claim 13, wherein while positional information of at least the first stage is measured with a position measurement system, movement of at least the first stage is controlled.

15. The exposure method according to claim 14, further comprising:

placing the first stage at an exchange position of the object, the exchange position being away from the projection optical system;

carrying the object, to which pre-alignment has been performed by a pre-alignment device, to above the first stage that is placed at the exchange position, with a carrier system that carries the object, the pre-alignment device being provided at the carrier system; and

controlling the first stage and/or the carrier system based on positional information of the depressed section, in order to load the object onto the first stage so that the object that is carried to above the first stage is placed in the depressed section.

16. The exposure method according to claim 15, wherein a positional relationship between the object to be loaded and the first stage is set based on the positional information of the depressed section so that the object is loaded without coming into contact with the upper surface of the first stage.

17. The exposure method according to claim 16, wherein the object is held in the depressed section so that the gap is substantially even.

18. The exposure method according to claim 15, wherein the positional information of the depressed section includes information on a center position or a shape of the depressed section.

20. A device manufacturing method, including:

a lithography process that uses the exposure method according to claim 10; and

a device formation process.