Exposure apparatus and exposure method, and device manufacturing method

• US 6,842,221 B1
• Filed: 02/04/2000
• Issued: 01/11/2005
• Est. Priority Date: 03/12/1999
• Status: Expired due to Fees

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: Shiraishi, Naomasa
• Primary Examiner(s): MATHEWS, ALAN A
• Application Number:
  US09/926,149
• Time in Patent Office: 1,803 Days
• Field of Search: 355/30, 355/53, 355/72, 355/75, 355/77, 356/237.4, 356/237.5, 430/5, 430/311, 430/396, 414/937, 414/940
• US Class Current: 355/30
• CPC Class Codes: G03F 7/70741 Handling masks outside exposure position, e.g. reticle libraries
• CPC Class Codes: G03F 7/7075 Handling workpieces outside exposure position, e.g. SMIF box
• CPC Class Codes: G03F 7/70866 of mask or workpiece
• CPC Class Codes: G03F 7/70933 Purge, e.g. exchanging fluid or gas to remove pollutants

Abstract

After a mask is carried into a reserve room for temporarily storing before carrying into a mask room filled with specific gas that has an impurity concentration lower than a first concentration (e.g. 1 ppb) and that has a characteristic of absorbing little exposure light, gas-replacement mechanisms replace gas in the reserve room with specific gas having an oxygen concentration not lower than the first concentration. Therefore, when subsequently carrying the mask into the mask room, impurities from the outside (including absorbent gas) can be substantially prevented from getting into the optical path inside the mask room. When replacing a wafer, gas in a reserve room is also replaced in the same way as the above.

Claims

1. An exposure apparatus that transfers a pattern of a mask onto a substrate by irradiating said mask with exposure light, the exposure apparatus comprising:

a sealed mask room that covers at least an optical path near said mask of the optical path of said mask to said substrate and that is filled with gas having a characteristic of absorbing little of said exposure light;

a sealed mask-reserve room, which temporarily contains said mask before being carried into said mask room, with at least one door through which said mask is transported;

a gas-replacement system connected to said mask-reserve room that supplies a specific gas to said mask-reserve room; and

a mask cleaning system that removes materials having absorption for exposure light and existing around said mask in said mask-reserve room.

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

a mask-transport system that transports said mask from said mask-reserve room through said door to said mask room.

3. An exposure apparatus according to claim 1, wherein

said mask cleaning system includes an energy-beam-emitting portion that irradiates said mask with an energy beam in an ultraviolet range, and said energy beam enters said mask-reserve room.

4. An exposure apparatus according to claim 3, wherein

a beam source of said energy-beam-emitting portion is an excimer lamp.

5. An exposure apparatus according to claim 3, wherein

said gas-replacement system replaces gas existing in said mask-reserve room with said specific gas by making said specific gas flow continuously.

6. An exposure apparatus according to claim 3, wherein

said gas-replacement system includes a pressure-reduction mechanism that is connected to said mask-reserve room and reduces pressure in said mask-reserve room.

7. An exposure apparatus according to claim 1, wherein

said exposure light is light having a wavelength not longer than 200 nm.

8. An exposure apparatus according to claim 1, wherein

said specific gas is substantially composed of gases selected from the group consisting of:

nitrogen, argon, helium, neon and krypton.

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

a substrate room constituted by a sealed room that covers at least an optical path near a substrate of the optical path of said exposure light from said mask to said substrate and that is filled with said specific gas.

10. An exposure apparatus according to claim 9, further comprising:

a substrate-reserve room constituted by a sealed room that is arranged adjacent to said substrate room and that temporarily stores said substrate before being carried into said substrate room; and

a gas-replacement mechanism connected to said substrate-reserve room that replaces gas in said substrate-reserve room with said specific gas.

11. An exposure apparatus that transfers a pattern of a mask onto a substrate by irradiating said mask with exposure light, the exposure apparatus comprising:

a sealed mask room that covers at least an optical path near said mask of the optical path of said mask to said substrate and that is filled with gas having a characteristic of absorbing little of said exposure light;

a sealed mask-reserve room, which temporarily contains said mask before being carried into said mask room, with at least one door through which said mask is transported;

a gas-replacement system connected to said mask-reserve room that supplies a specific gas to said mask-reserve room; and

a removing system connected to said mask-reserve room that removes materials having absorption for exposure light and existing around said mask.

12. An exposure apparatus according to claim 11, further comprising:

a mask-transport system that transports said mask from said mask-reserve room through said door to said mask room.

13. An exposure apparatus according to claim 11, further comprising:

a gas-replacement mechanism in said sealed mask-reserve room that replaces gas existing in a space between said mask and a pellicle disposed in a vicinity of said mask with said specific gas, wherein

said gas-replacement mechanism replaces said gas through gas vents on a pellicle-frame disposed in between said mask and said pellicle.

14. An exposure apparatus according to claim 13, wherein

said gas-replacement mechanism spends a time of not less than 10 seconds in performing said gas replacement.

15. An exposure apparatus according to claim 13, wherein

said removing system includes a pressure-reduction mechanism that reduces pressure in said mask-reserve room.

16. An exposure apparatus according to claim 11, wherein

in a chamber constituting said mask-reserve room, a delivery port is provided into and from which a sealed-type mask container containing said mask and having a door that can be opened and closed is loaded and unloaded, and

in said mask-reserve room, an open-close mechanism is provided that opens and closes the door of said mask container to isolate the inside of said mask-reserve room from the outside.

17. An exposure apparatus according to claim 16, wherein

said mask container is a bottom-open-type mask container on the bottom of which said door is provided.

18. An exposure apparatus according to claim 11, wherein

said exposure light is light having a wavelength not longer than 200 nm.

19. An exposure apparatus according to claim 11, wherein

said specific gas is substantially composed of gases selected from the group consisting of:

nitrogen, argon, helium, neon and krypton.

20. An exposure apparatus according to claim 11, further comprising:

a substrate room constituted by a sealed room that covers at least an optical path near a substrate of the optical path of said exposure light from said mask to said substrate and that is filled with said specific gas.

21. An exposure apparatus according to claim 20, further comprising:

a substrate-reserve room constituted by a sealed room that is arranged adjacent to said substrate room and that temporarily stores said substrate before being carried into said substrate room; and

a gas-replacement mechanism connected to said substrate-reserve room that replaces gas in said substrate-reserve room with said specific gas.

22. An exposure apparatus according to claim 11, wherein

said removing system includes a pressure-reduction mechanism that is connected to said mask-reserve room and reduces pressure in said mask-reserve room.

23. An exposure apparatus according to claim 11, wherein

said removing system includes an energy-beam-emitting portion that irradiates said mask with an energy beam in an ultraviolet range, and

said energy beam reaches inside said mask-reserve room.

24. An exposure apparatus according to claim 23, wherein

a source of said energy-beam-emitting portion is an excimer lamp.

25. An exposure method that transfers a pattern of a mask onto a substrate by irradiating said mask with exposure light, the exposure method comprising:

filling a sealed space that covers at least an optical path near said mask of the optical path of said exposure light from said mask to said substrate with gas having a characteristic of absorbing little of said exposure light;

temporarily storing said mask in a reserve room before carrying said mask into said sealed space;

replacing gas in said reserve room, in which said mask is existing, with said low absorbent gas, and cleaning said mask in said reserve room to remove materials having absorption for exposure light and existing around said mask; and

transporting said mask to a predetermined position in said sealed space and transferring said pattern onto said substrate.

26. An exposure method according to claim 25, wherein

said cleaning of mask is performed by irradiating a beam in an ultraviolet range to said mask.

27. An exposure method according to claim 25, wherein

said gas-replacement is performed by continuous flow of said specific gas.

28. An exposure method according to claim 25, wherein

said mask cleaning is performed by reduction of pressure in said mask-reserve room.

29. An exposure method according to claim 25, wherein

said exposure light is light having a wavelength not longer than 200 nm.

30. An exposure method according to claim 25, wherein

said specific gas is substantially composed of gases selected from the group consisting of:

nitrogen, argon, helium, neon and krypton.

31. A device manufacturing method including a lithographic process, wherein

in said lithographic process, exposure is performed using an exposure method according to claim 25.

32. An exposure method that transfers a pattern of a mask onto a substrate by irradiating said mask with exposure light, the exposure method comprising:

filling a sealed space that covers at least an optical path near said mask of the optical path of said exposure light from said mask to said substrate with gas having a characteristic of absorbing little of said exposure light;

temporarily storing said mask in a reserve room before carrying said mask into said sealed space;

replacing gas in said reserve room, in which said mask is existing, with said low absorbent gas;

removing materials having absorption for exposure light and existing around said mask in said mask-reserve room; and

transporting said mask to a predetermined position in said sealed space and transferring said pattern onto said substrate.

33. An exposure method according to claim 32, further comprising:

replacing gas in a space between said mask and a pellicle disposed in a vicinity of said mask with said low absorbent gas, wherein

said gas replacement of said space between said mask and said pellicle is performed through gas vents on a pellicle-frame disposed in between said mask and said pellicle.

34. An exposure method according to claim 33, wherein

said gas replacement of said space between said mask and said pellicle spends time not less than 10 seconds.

35. An exposure method according to claim 32, wherein

said mask is transported to said reserve room within a scaled-type mask container having a door that can be opened and closed, and said mask container is opened and closed by an open-close mechanism provided by said reserve room.

36. An exposure method according to claim 35, wherein

said mask container is a bottom-open-type mask container on the bottom of which said door is provided.

37. An exposure method according to claim 32, wherein

said exposure light is light having a wavelength not longer than 200 nm.

38. An exposure method according to claim 32,

wherein said specific gas is substantially composed of gases selected from the group consisting of:

nitrogen, argon, helium, neon and krypton.

39. A device manufacturing method including a lithographic process, wherein

in said lithographic process, exposure is performed using an exposure method according to claim 32.

40. An exposure method according to claim 32, wherein

said removal of materials is performed by irradiating a beam in an ultraviolet range to said mask.

41. An exposure method according to claim 32, wherein

said removal of materials is made by reduction of pressure in said mask-reserve room.