Lithographic apparatus and device manufacturing method

• US 20070242245A1
• Filed: 04/03/2007
• Published: 10/18/2007
• Est. Priority Date: 04/06/2006
• Status: Active Grant

• Current Assignee: ASML Netherlands BV (ASML Holding NV)
• Original Assignee: ASML Netherlands BV (ASML Holding NV)
• Inventors: Van Baren, Martijn, Van Der Meulen, Frits, Jansen, Rob, De Jong, Frederik, Wijckmans, Maurice, Ottens, Joost, Leenders, Martinus Hendrikus, Simons, Wilhelmus Franciscus, Van Gompel, Edwin Augustinus, Kusters, Gerardus Adrianus, Cuijpers, Martinus Agnes, Cadee, Theodorus, Smeets, Martin
• Granted Patent: US 8,913,228 B2
• Time in Patent Office: Days
• US Class Current: 355/53
• CPC Class Codes: F16L 55/053 the gas in the reservoir being separated from the fluid in the pipe
• 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 7/70783 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
• CPC Class Codes: G03F 7/70875 Temperature, e.g. temperature control of masks or workpieces via control of stage temperature

Abstract

A lithographic apparatus is disclosed that is arranged to project a pattern from a patterning device onto a substrate, the lithographic apparatus has a substrate table configured to hold a substrate. The substrate table includes a conditioning system configured to hold a conditioning fluid and to condition the substrate table. The conditioning system includes a pressure damper that is in fluid communication with the conditioning system and is arranged to dampen a pressure variation in the conditioning system.

Claims

1. A lithographic apparatus arranged to project a pattern from a patterning device onto a substrate, the lithographic apparatus comprising an object, the object comprising a conditioning system configured to hold a conditioning fluid and to condition the object, the conditioning system comprising a pressure damper in fluid communication with the conditioning system and arranged to dampen a pressure variation in the conditioning system and/or isolate the conditioning fluid within said object from conditioning fluid outside of said object.

2. The apparatus of claim 1, wherein the pressure damper is positioned in the vicinity of the object.

3. The apparatus of claim 2, wherein the pressure damper is positioned in an object carrier arranged to carry the object.

4. The apparatus of claim 1, wherein the conditioning system comprises a conditioning fluid supply device configured to transport the conditioning fluid to the object.

5. The apparatus of claim 4, wherein the pressure damper is in fluid communication with the supply device.

6. The apparatus of claim 1, wherein the conditioning system comprises a conditioning fluid removal device configured to transport the conditioning fluid away from the object.

7. The apparatus of claim 6, wherein the pressure damper is in fluid communication with the removal device.

8. The apparatus of claim 1, wherein the pressure damper comprises a housing having two compartments separated by a moveable member, wherein one of the compartments is connected to the conditioning system.

9. The apparatus of claim 8, wherein the moveable member is a flexible membrane.

10. The apparatus of claim 8, wherein the moveable member is a moveable piston.

11. The apparatus of claim 8, wherein the other compartment holds a compressible medium.

12. The apparatus of claim 1, wherein said pressure damper comprises:

a moveable member in fluid communication, on one side, with said conditioning system; and

an actuator connected to said moveable member and configured to apply a constant force to said moveable member.

13. The apparatus of claim 12, further comprising control electronics configured to return said flexible membrane to a neutral position.

14. The apparatus of claim 13, wherein said control electronics operate at low frequency.

15. The apparatus of claim 14, wherein said frequency is below 0.1 Hz.

16. The apparatus of claim 1, wherein said pressure damper is an active pressure damper and said apparatus comprises:

a pressure sensor constructed and arranged to measure the pressure of said conditioning fluid, and a controller constructed and arranged to drive said pressure damper on the basis of signals from said pressure sensor, wherein said pressure damper is configured to apply a substantially equal and opposite pressure to a pressure variation measured by said pressure sensor.

17. The apparatus of claim 16, further comprising a passive damper.

18. The apparatus of claim 1, wherein said conditioning system is configured to circulate the conditioning fluid at least partly in a loop around said object without leaving said object.

19. The apparatus of claim 18, wherein said conditioning system comprises a pump mounted to said object, said pump being constructed and arranged to pump the conditioning fluid around said loop.

20. The apparatus of claim 18, wherein said conditioning system further comprises a heater mounted to said object, said heater being constructed and arranged to condition said conditioning fluid.

21. The apparatus of claim 18, wherein said conditioning system further comprises a first conduit constructed and arranged to add conditioning fluid to said loop from outside of said object, and a second conduit constructed and arranged to remove conditioning fluid from said loop to outside of said object.

22. The apparatus of claim 1, further comprising at least one flow restriction in a flow path of the conditioning fluid in said conditioning system.

23. The apparatus of claim 22, wherein said flow restriction is in a part of said flow path within said object.

24. The apparatus of claim 22, wherein said flow restriction is positioned in said flow path at or adjacent a position at which the conditioning fluid enters and/or exits said object.

25. The apparatus of claim 22, wherein said flow restriction is positioned in a part of said flow path in which the conditioning fluid substantially flows towards said object.

26. The apparatus of claim 22, further comprising a pump configured to pump the conditioning fluid, said pump being positioned in a part of said flow path in which the conditioning fluid substantially flows away from said object.

27. The apparatus of claim 26, wherein said pump is a positive displacement pump.

28. The apparatus of claim 1, further comprising two pumps in a flow path of the conditioning fluid, a first of said two pumps being positioned in said flow path at a position in which the conditioning fluid substantially flows towards said object, and a second of said two pumps being positioned in said flow path at a position in which the conditioning fluid substantially flows away from said object.

29. The apparatus of claim 1, wherein said object is a substrate table configured to hold a substrate or a mask table configured to hold a mask.

30. A lithographic apparatus arranged to project a pattern from a patterning device onto a substrate, the lithographic apparatus comprising a substrate table configured to hold a substrate, and an object comprising a conditioning system configured to condition the object by pumping a conditioning fluid around a loop using a pump mounted to the object.

31. The apparatus of claim 30, further comprising a conditioning fluid conditioner constructed and arranged to change the temperature of said conditioning fluid.

32. The apparatus of claim 31, wherein said conditioning fluid conditioner is a heater mounted to said object.

33. The apparatus of claim 30, wherein said conditioning system is configured such that a majority of conditioning fluid in said loop is re-circulated within said loop and a minority of conditioning fluid in said loop is removed from said loop for conditioning outside of said object before being returned to said loop.

34. The apparatus of claim 30, wherein said object is said substrate table or a mask table configured to hold a mask.

35. A lithographic apparatus arranged to project a pattern from a patterning device onto a substrate, the lithographic apparatus comprising a substrate table configured to hold a substrate, and an object comprising a conditioning system configured to condition the object, wherein said conditioning system comprises an active pressure damper, a pressure sensor for measuring the pressure of said conditioning fluid, and a controller for driving said active pressure damper on the basis of signals from said pressure sensor, said active pressure damper being configured to apply a substantially equal and opposite pressure to a pressure variation measured by said pressure sensor.

36. A lithographic apparatus arranged to project a pattern from a patterning device onto a substrate, the lithographic apparatus comprising a substrate table configured to hold a substrate, and an object comprising a conditioning system configured to condition the object by pumping a conditioning fluid around a flow path in said object, said flow path comprising at least one flow restriction.

37. The apparatus of claim 36, wherein said flow restriction is positioned in said flow path in said object.

38. The apparatus of claim 36, wherein said flow restriction is positioned at or adjacent an entry or exit position at which, in use, conditioning fluid respectively enters or exits said object.

39. The apparatus of claim 36, further comprising at least one pump constructed and arranged to pump conditioning fluid in said flow path, said pump being positioned either (i) in said flow path at a position at which the conditioning fluid substantially flows towards said object, if said flow restriction is in said flow path at a position at which the conditioning fluid substantially flows away from said object, or (ii) in said flow path at a position at which the conditioning fluid substantially flows away from said object, if said flow restriction is in said flow path at a position at which the conditioning fluid substantially flows towards said object.

40. A lithographic apparatus arranged to project a pattern from a patterning device onto a substrate, the lithographic apparatus comprising a substrate table configured to hold a substrate, the substrate table comprising a conditioning system configured to condition the substrate table by pumping a conditioning fluid through said substrate table, said conditioning system comprising two pumps in a flow path of conditioning fluid, a first of said two pumps being positioned in said flow path at a position in which the conditioning fluid substantially flows towards said substrate table, and a second of said two pumps being positioned in said flow path at a position in which the conditioning fluid substantially flows away from said substrate table.

41. A lithographic apparatus arranged to project a pattern from a patterning device onto a substrate, the lithographic apparatus comprising a substrate table configured to hold a substrate, the substrate table comprising a conditioning system configured to hold a conditioning fluid and to condition the substrate table, wherein the conditioning system comprises a conditioning fluid supply device configured to transport the conditioning fluid to the substrate table, a conditioning fluid removal device configured to transport the conditioning fluid away from the substrate table, a first pressure damper in fluid communication with the supply device and a second pressure damper in fluid communication with the removal device, the pressure dampers being arranged to dampen a pressure variation in the conditioning system and/or isolate the conditioning fluid in said substrate table from the conditioning fluid outside of said substrate table.

42. A method of manufacturing a device, the method comprising:

projecting a patterned beam of radiation onto a target portion of a substrate;

conditioning the substrate using a conditioning system; and

dampening a pressure variation in the conditioning system.