Lithographic apparatus and device manufacturing method

• US 20050259233A1
• Filed: 05/21/2004
• Published: 11/24/2005
• Est. Priority Date: 05/21/2004
• Status: Active Grant

• Current Assignee: ASML Netherlands BV (ASML Holding NV)
• Original Assignee: ASML Netherlands BV (ASML Holding NV)
• Inventors: Streefkerk, Bob, Mertens, Jeroen Johannes Sophia Maria, Hoogendam, Christiaan Alexander, Zaal, Koen Jacobus Johannes Maria, Cuperus, Minne, Cox, Henrikus Herman Marie
• Granted Patent: US 7,486,381 B2
• Time in Patent Office: Days
• 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 7/70641 Focus
• CPC Class Codes: G03F 7/70783 Handling stress or warp of chucks, masks or workpieces, e.g. to compensate for imaging errors or considerations related to warpage of masks or workpieces due to their own weight

Abstract

An immersion lithographic apparatus includes a liquid supply system member configured to contain a liquid in a space between a projection system of the lithographic apparatus and the substrate and a liquid supply system member compensator arranged to compensate an interaction between the liquid supply system member and substrate table.

Claims

1. A lithographic apparatus comprising:

an illumination system arranged to condition a radiation beam;

a support structure configured to hold a patterning device, the patterning device being capable of imparting the radiation beam with a pattern in its cross-section, thus providing a patterned radiation beam;

a substrate table configured to hold a substrate;

a projection system arranged to project the patterned radiation beam onto a target portion of the substrate;

a liquid supply system member configured to contain a liquid in a space between the projection system and the substrate; and

a liquid supply system member compensator arranged to compensate for an interaction between the liquid supply system member and the substrate table.

2. A lithographic apparatus according to claim 1, wherein the interaction comprises the weight of the liquid supply system member.

3. A lithographic apparatus according to claim 1, wherein the liquid supply system member compensator comprises a focus calibration device configured to compensate a relative position of the substrate and a plane of best focus of the lithographic apparatus according to compensation data.

4. A lithographic apparatus according to claim 3, wherein the compensation data is derived from the output of a substrate table geometry measuring device configured to determine a surface height profile, a surface tilt profile, or both of the substrate table when disturbed by the interaction with the liquid supply system member, the surface height profile being defined in a direction substantially parallel to the optical axis of a final element of the projection system and the surface tilt profile being defined with respect to one or two orthogonal axes of a plane substantially perpendicular to the optical axis of the final element of the projection system.

5. A lithographic apparatus according to claim 4, wherein the substrate table geometry measuring device is configured to determine the surface height profile, the surface tilt profile, or both of the substrate table as a function of the position of the liquid supply system member relative to the substrate table in a plane substantially perpendicular to the optical axis of the final element of the projection system.

6. A lithographic apparatus according to claim 3, wherein the compensation data is derived from a mechanical mathematical model of the substrate table, which is arranged to forecast substrate table disturbance as a function of a position dependent applied force.

7. A lithographic apparatus according to claim 3, wherein the compensation data is derived from an analysis of an exposed focus test pattern, arranged to reveal the extent of focus error as a function of position.

8. A lithographic apparatus according to claim 7, wherein the exposed focus test pattern is imaged on a reference lithography apparatus subjected to forces substantially equivalent to the interaction between the liquid supply system member and the substrate table.

9. A lithographic apparatus according to claim 1, wherein the liquid supply system member compensator comprises a liquid supply system member suspension device capable of applying a force to the liquid supply system member to at least partially compensate for the interaction between the liquid supply system member and the substrate table.

10. A lithographic apparatus according to claim 9, wherein the liquid supply system member suspension device is configured to couple to a frame supporting at least a part of the projection system, the frame being capable of supporting via the coupling at least part of the reaction to the force applied by the liquid supply system member suspension device to the liquid supply system member.

11. A lithographic apparatus according to claim 9, wherein the liquid supply system member suspension device is configured to couple to the projection system, the projection system being capable of supporting via the coupling at least part of the reaction to the force applied by the liquid supply system member suspension device to the liquid supply system member.

12. A lithographic apparatus according to claim 9, further comprising a liquid supply system member suspension device controller configured to apply a control force to the liquid supply system member, via the liquid supply system member suspension device, according to data representing the magnitude of the interaction between the liquid supply system member and the substrate table.

13. A lithographic apparatus according to claim 9, wherein the interaction comprises the weight of the liquid supply system member.

14. A lithographic apparatus according to claim 9, wherein the interaction comprises an external force.

15. A lithographic apparatus according to claim 9, wherein the interaction comprises an external position dependent force.

16. A lithographic apparatus according to claim 9, further comprising a liquid supply system member suspension device controller and a liquid supply system member position determining device, the liquid supply system member suspension device controller being configured to apply a control force to the liquid supply system member, via the liquid supply system member suspension device, based on a position of the liquid supply system member as measured by the liquid supply system member position determining device.

17. A lithographic apparatus according to claim 16, wherein the liquid supply system member position determining device determines a position of the liquid supply system member, relative to the projection system or a frame supporting at least a part of the projection system, in a direction substantially parallel to the optical axis of the projection system.

18. A lithographic apparatus according to claim 16, wherein the liquid supply system member position determining device determines a position of the liquid supply system member in a direction substantially perpendicular to the optical axis of the projection system.

19. A lithographic apparatus according to claim 16, wherein the control force is applied so as to compensate for forces arising from a liquid supply system member guiding member attached between the liquid supply system member and a frame supporting at least a part of the projection system.

20. A lithographic apparatus according to claim 9, further comprising a substrate table force compensator configured to determine the magnitude of the interaction between the liquid supply system member and the substrate table and transmit data representing the magnitude to the liquid supply system member suspension device.

21. A lithographic apparatus according to claim 9, wherein the liquid supply system member suspension device operates by means of at least one mechanism selected from the following list:

an electromagnetic force using the Lorentz principle, an electromagnetic force using the reluctance principle, a bellows, and a mechanical spring.

22. A lithographic apparatus according to claim 1, comprising a liquid supply system member suspension device configured to lift the liquid supply system member clear of the substrate table for substrate table exchange.

23. A lithographic apparatus according to claim 1, comprising a liquid supply system member suspension device configured to position the liquid supply system member clear of the substrate table in a distal safety position in response to a system failure.

24. A lithographic apparatus according to claim 23, wherein the liquid supply system member suspension device comprises:

a housing comprising a pressure medium;

a first piston slidably engaged within a first wall of the housing nearest the liquid supply system member, and coupled to the liquid supply system member;

a second piston, forced towards the first piston by a pre-tensioned spring, and slidably engaged within a second wall of the housing opposite the first wall; and

a pressure regulator configured to control the pressure within the housing, the pressure acting to apply a force to the first piston in a direction substantially parallel to the optical axis of the projection system and directed towards the liquid supply system member, and apply a force in the opposite direction to the second piston, wherein,

in a normal operating mode, the first and second pistons are arranged to interact with each other, the pressure regulator being arranged to control the vertical position of the liquid supply system member by varying the pressure within the housing;

at pressures within the housing below a lower threshold pressure, the pre-tension in the spring is arranged to dominate the motion of the second piston, which forces the first piston and the liquid supply system member into a safety position clear of the substrate table; and

at pressures within the housing above an upper threshold pressure, the pressure medium force is arranged to dominate and forces the first piston clear of the second piston and the liquid supply system member into a safety position clear of the substrate table.

25. A device manufacturing method comprising:

containing a liquid in a space between a projection system of a lithographic apparatus and a substrate table using a liquid supply system member;

compensating for an interaction between the liquid supply system member and the substrate table; and

projecting a patterned radiation beam through the liquid onto a target portion of the substrate using the projection system.

26. A device manufacturing method according to claim 25, comprising compensating a relative position of the substrate and a plane of best focus of the lithographic apparatus according to compensation data.

27. A device manufacturing method according to claim 26, wherein the compensation data is derived from determining a surface height profile, a surface tilt profile, or both of the substrate table when disturbed by the interaction with the liquid supply system member, the surface height profile being defined in a direction substantially parallel to the optical axis of a final element of the projection system and the surface tilt profile being defined with respect to one or two orthogonal axes of a plane substantially perpendicular to the optical axis of the final element of the projection system.

28. A device manufacturing method according to claim 27, comprising determining the surface height profile, the surface tilt profile, or both of the substrate table as a function of a horizontal position of the liquid supply system member relative to the substrate table.

29. A device manufacturing method according to claim 26, wherein the compensation data is derived from a mechanical mathematical model of the substrate table, which is arranged to forecast substrate table disturbance as a function of a position dependent applied force.

30. A device manufacturing method according to claim 26, wherein the compensation data is derived from an analysis of an exposed focus test pattern, arranged to reveal the extent of focus error as a function of position.

31. A device manufacturing method according to claim 25, comprising applying a force to the liquid supply system member to at least partially compensate for the interaction between the liquid supply system member and the substrate table.

32. A device manufacturing method according to claim 31, wherein the interaction comprises the weight of the liquid supply system member, an external force, an external position dependent force, or any combination of the foregoing.

33. A device manufacturing method according to claim 31, comprising applying a control force to the liquid supply system member based on a position of the liquid supply system member.

34. A device manufacturing method according to claim 33, comprising determining a position of the liquid supply system member, relative to the projection system or a frame supporting at least a part of the projection system, in a direction substantially parallel to the optical axis of the projection system, determining a position of the liquid supply system member in a direction substantially perpendicular to the optical axis of the projection system, or both.

35. A device manufacturing method according to claim 25, comprising lifting the liquid supply system member clear of the substrate table for substrate table exchange.

36. A device manufacturing method according to claim 25, comprising positioning the liquid supply system member clear of the substrate table in a distal safety position in response to a system failure.

37. A lithographic apparatus focus calibration method, comprising:

containing a liquid in a space between a projection system of a lithography apparatus and a substrate table of the lithography apparatus using a liquid supply system member;

determining a surface height profile, a surface tilt profile, or both of the substrate table when disturbed by an interaction with the liquid supply system member, the surface height profile being defined in a direction substantially parallel to the optical axis of a final element of the projection system and the surface tilt profile being defined with respect to one or two orthogonal axes of a plane substantially perpendicular to the optical axis of the final element of the projection system; and

determining compensation data to compensate the relative position of the substrate and the plane of best focus of the lithography apparatus.

38. A lithographic apparatus focus calibration method, comprising:

projecting a radiation beam imparted with a focus test pattern, through a liquid, onto a target portion of a substrate, using a projection system of a lithography apparatus;

analyzing the projected focus test pattern on the substrate to determine focus error at a plurality of positions; and

determining compensation data to compensate the relative position of the substrate and the plane of best focus of the lithography apparatus.