Exposure apparatus, substrate processing system, and device meanufacturing method

• US 20030117596A1
• Filed: 12/05/2002
• Published: 06/26/2003
• Est. Priority Date: 04/06/2001
• Status: Active Grant

• Current Assignee: Nikon Corporation
• Original Assignee: Nikon Corporation
• Inventors: Nishi, Kenji
• Granted Patent: US 6,853,443 B2
• Time in Patent Office: Days
• US Class Current: 355/72
• CPC Class Codes: G03F 7/70766 Reaction force control means, e.g. countermass
• CPC Class Codes: G03F 7/70833 Mounting of optical systems, e.g. mounting of illumination system, projection system or stage systems on base-plate or ground
• CPC Class Codes: G03F 7/709 Vibration, e.g. vibration detection, compensation, suppression or isolation

Abstract

A first main body unit for supporting a substrate stage is supported at four points by vibration isolators, and a second main body unit is supported on the first main body unit at three points by second vibration isolators. This allows the first main body unit and the substrate stage to be supported in a stable manner with high rigidity, and for example, allows maintenance operations on the stage portion from the back side of the apparatus (−X side), which is not possible when the first main body unit is supported at three points. In addition, since the apparatus comprises vibration isolation units that are connected in series in two platforms, such an arrangement has a great effect of suppressing background vibration from the floor surface. Accordingly, exposure with high precision can be performed which improves the yield of devices, and the time reduced for maintenance operations can improve the operation rate of the apparatus, consequently leading to an improvement in productivity of devices as end products.

Claims

1. An exposure apparatus that transfers a pattern formed on a mask onto a substrate via a projection optical system, the exposure apparatus comprising:

a mask stage that holds the mask;

a substrate stage that holds the substrate;

a first main body unit that supports at least one of the mask stage and the substrate stage;

four first vibration isolators that support the first main body unit at four points and isolate vibration in the first main body unit;

a second main body unit that supports the projection optical system; and

three second vibration isolators that support the second main body unit at three points on different straight lines on the first main body unit and isolate vibration in the second main body unit.

2. The exposure apparatus of claim 1 wherein the four first vibration isolators support the first main body unit at each corner of in a square shape.

3. The exposure apparatus of claim 1 wherein each of the second vibration isolators is an active vibration isolator that includes an actuator.

4. The exposure apparatus of claim 3 wherein provided in the second main body unit are

at least one of an interferometer that measures a position of at least one of the stages, a position detector that measures at least a position of the substrate in an optical axis direction of the projection optical system and a tilt, and a mark detection system that detects a position of marks on the substrate, and

a vibration sensor that detects vibration in the second main body unit, and the exposure apparatus further comprises:

a controller that performs posture control of the second main body unit by controlling the actuators based on an output of the vibration sensor.

5. The exposure apparatus of claim 4 wherein the controller performs the posture control in direction of three degrees of freedom, in the optical axis direction of the projection optical system and in rotational directions around two orthogonal axes within a plane perpendicular to the optical axis.

6. The exposure apparatus of claim 1 wherein the second main body unit supports the projection optical system at three points via a kinematic support mechanism.

7. The exposure apparatus of claim 1 wherein the first main body unit holds the mask stage.

8. The exposure apparatus of claim 1 wherein

the exposure apparatus has a first substrate stage that holds a first substrate and a second substrate stage that holds a second substrate serving as the substrate stage, and

the first main body unit holds the first substrate stage and the second substrate stage.

27. A device manufacturing method including a lithographic process, wherein in the lithographic process exposure is performed using the exposure apparatus according to claim 1.

9. An exposure apparatus that transfers a pattern formed on a mask onto a substrate via a projection optical system, the exposure apparatus comprising:

an optical system holding unit that holds the projection optical system;

a stage chamber where a substrate chamber that houses a substrate stage holding the substrate is formed inside, along with a first opening in which members on an image plane side of the projection optical system can be inserted; and

a first connecting member that connects a periphery portion of the first opening of the stage chamber to a circumferential portion of the projection optical system while isolating the inside of the substrate chamber from outside air in a sealed state, the first connecting member having flexibility.

10. The exposure apparatus of claim 9 wherein the first connecting member is a flexible bellows.

11. The exposure apparatus of claim 9 wherein the inside of the substrate chamber is filled with at least one of an inert gas and nitrogen gas.

12. The exposure apparatus of claim 9 wherein

a second opening is further formed in the stage chamber, and

the optical system holding unit has a third opening formed at a position opposing the second opening and a holding member that holds the projection optical system, and the exposure apparatus further comprises:

a second connecting member that connects the stage chamber and the holding member in a sealed state isolated from outside air at a periphery portion of the second opening and the third opening opposing the second opening, the second connecting member having flexibility;

a detection system that detects positional information on at least one of the substrate and marks on the substrate, the detection system having a barrel portion inserted in a space formed by the second opening, the third opening, and the second connecting member, and a sensor head portion divided from the barrel portion; and

a glass plate that isolates the inside of the space from the outside air, the glass plate fixed to a surface of the holding member on the opposite side of the stage chamber.

13. The exposure apparatus of claim 12 wherein the second connecting member is a flexible bellows.

14. The exposure apparatus of claim 12 wherein a seal member seals a space between the glass plate and the holding member.

15. The exposure apparatus of claim 14 wherein the seal member is one of an O-ring and a viscous member that complies with chemically clean requirements.

16. The exposure apparatus of claim 9 wherein

the projection optical system has a tilt drive portion including a tilt drivable lens located closest to an image plane side, and a fixed portion integrally fixed to the optical system holding unit, and

the tilt drive portion and the fixed portion are connected with a connecting member, the connecting member having flexibility.

17. The exposure apparatus of claim 16 wherein

the tilt portion has the lens and a holding frame that holds the lens, and

a seal member seals a space between the lens and the holding frame.

18. The exposure apparatus of claim 17 wherein the seal member is one of an O-ring and a viscous member that complies with chemically clean requirements.

19. The exposure apparatus of claim 9 wherein the exposure apparatus further comprises a gas blowing portion that blows inert gas inside the substrate chamber within the stage chamber, the blowing portion detachably connected to the stage chamber.

20. The exposure apparatus of claim 9 wherein

the exposure apparatus further comprises a supporting unit that supports the optical holding unit via a vibration isolator, whereby

the supporting unit supports the stage chamber by suspension.

28. A device manufacturing method including a lithographic process, wherein in the lithographic process exposure is performed using the exposure apparatus according to claim 9.

21. An exposure apparatus that transfers a pattern formed on a mask onto a substrate via a projection optical system, the exposure apparatus comprising:

a stage chamber where members on an image plane side of the projection optical system are inserted and a sealed chamber that houses a substrate stage holding the substrate is formed inside;

a first main body unit that supports the stage chamber by suspension; and

reaction bars that absorb reaction force occurring when the substrate stage is driven, one end of the reaction bar being connected to the stage chamber.

22. The exposure apparatus of claim 21 wherein the exposure apparatus further comprises a reaction frame fixed to a floor surface, the reaction frame being connected to the other end of the reaction bar.

23. The exposure apparatus of claim 21 wherein

the stage chamber has a chamber main body that houses the substrate stage where an opening portion is formed on at least one side of a side surface of the chamber main body, and a cover that covers the opening portion, the cover protruding outside the chamber main body, and

at least a part of an interferometer that measures a position of the substrate stage is arranged in a space inside the cover.

24. The exposure apparatus of claim 23 wherein

a first substrate stage and a second substrate stage serving as the substrate stage are housed within the chamber main body where the opening portion is formed on one side and the other side of a side surface of the chamber main body, respectively,

the cover is arranged in twosome corresponding to the two opening portions, and

at least a part of two interferometers that individually measure positions of the first and the second substrate stages are arranged, respectively, within each of the covers.

25. The exposure apparatus of claim 23 wherein the exposure apparatus further comprises:

a second main body unit that holds the projection optical system, the second main body unit mounted on the first main body unit via a vibration isolator; and

a sensor column that supports the second main body unit by suspension while holding at least the interferometers arranged inside the stage chamber, and

a length of the sensor column in a direction perpendicular to the side surface of the chamber main body where the opening portion is formed, is set larger than the chamber main body.

29. A device manufacturing method including a lithographic process, wherein in the lithographic process exposure is performed using the exposure apparatus according to claim 21.

26. An exposure apparatus that transfers a pattern formed on a mask onto a substrate via a projection optical system, the exposure apparatus comprising:

a stage chamber where a substrate chamber that houses a substrate stage holding the substrate is formed inside, along with a first opening in which members on an image plane side of the projection optical system can be inserted; and

an optical system holding unit where a second opening is formed at a position opposing the first opening, the optical system holding unit having a holding member for holding the projection optical system;

a connecting member that connects a periphery portion of the first opening of the stage chamber to the second opening of the holding member;

a cover that covers a circumferential portion on an object surface side of the projection optical system, one end of the cover being connected to a surface of the holding member opposite to the stage chamber;

a planar glass mounted on an opening edge surface of the cover via a double-structured O-ring; and

an exhaust pipe that exhausts gas inside a ring-shaped space enclosed by the double structured O-ring, the planar glass, and the cover, the exhaust pipe being connected to the space via the cover.

30. A device manufacturing method including a lithographic process, wherein in the lithographic process exposure is performed using the exposure apparatus according to claim 26.

31. A substrate processing system that performs a predetermined process on a substrate, the substrate processing system comprising:

an exposure apparatus comprising an exposure apparatus main body that forms a predetermined pattern on the substrate by exposure, the exposure apparatus main body having a stage chamber that houses a substrate stage holding the substrate and a main unit that detachably supports the stage chamber by suspension, and a total chamber that houses the exposure apparatus main body almost entirely;

a substrate processor that performs at least one of resist coating and development on the substrate; and

an interface section that connects the total chamber and the substrate processor inline, the interface section being freely detachable to the total chamber and the substrate processor, with a substrate carriage system housed inside.