OPTICAL APPARATUS WITH ADJUSTABLE ACTION OF FORCE ON AN OPTICAL MODULE

• US 20110085239A1
• Filed: 12/08/2010
• Published: 04/14/2011
• Est. Priority Date: 06/10/2008
• Status: Active Grant

• Current Assignee: CARL Zeiss SMT GmbH (Carl-Zeiss-Stiftung)
• Original Assignee: CARL Zeiss SMT GmbH (Carl-Zeiss-Stiftung)
• Inventors: Kwan, Yim-Bun Patrick
• Granted Patent: US 8,964,165 B2
• Time in Patent Office: Days
• US Class Current: 359/503
• CPC Class Codes: G02B 7/003 Alignment of optical elements G02B7/001, G02B7/002 take precedence; for mirrors G02B7/1822
• CPC Class Codes: G02B 7/028 with means for compensating for changes in temperature or for controlling the temperature; thermal stabilisation
• CPC Class Codes: G03F 7/70141 Illumination system adjustment, e.g. adjustments during exposure or alignment during assembly of illumination system
• CPC Class Codes: G03F 7/70816 Bearings
• 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 7/70975 Assembly, maintenance, transport or storage of apparatus

Abstract

The disclosure pertains to an optical apparatus, in particular for microlithography, that includes an optical module, a support structure and a connection apparatus. The connection apparatus includes at least one connection unit which includes a first connector part and a second connector part. The first connector part is connected to the optical module, and the second connector part is connected to the support structure.

Claims

1. An optical apparatus, comprising:

an optical module;

a support structure; and

a connection apparatus, comprising;

a connection unit, comprising;

a first connector part connected to the optical module;

a second connector part connected to the support structure; and

at least a portion of a positioning device configured to act on the first and second connector parts,

wherein;

the connection unit has an adjustment state and an installed state;

the first connector part has a first contact surface with a first main curvature defining a first main curvature axis;

the second connector part has a second contact surface with a second main curvature defining a second main curvature axis;

the second main curvature is matched to the first main curvature;

in the installed state of the connection unit, the first contact surface contacts the second contact surface;

in the adjustment state of the connection unit, a narrow gap between the first and second contact surfaces is maintained in a non-contact manner so that a compensating motion between the first and second contact surfaces about the first main curvature axis is possible without the occurrence of any action of force between the first and second connector parts resulting from the compensating motion; and

the optical apparatus is configured to be used in microlithography.

2. The optical apparatus according to claim 1, wherein:

the positioning device comprises a force generation device; and

in the adjustment state of the connection unit, the force generation device maintains the narrow gap between the first and second contact surfaces by applying a force of attraction between the optical module and the support structure.

3. The optical apparatus according to claim 2, wherein, in the adjustment state of the connection unit, the force generation device maintains the narrow gap between the first and second contact surfaces by applying the force of attraction between the first and second connector parts.

4. The optical apparatus according to claim 1, wherein:

the positioning device comprises a force generation device; and

in the adjustment state of the connection unit, the force generation device maintains the narrow gap between the first and second contact surfaces by applying a force of repulsion between the optical module and the support structure.

5. The optical apparatus according to claim 4, wherein, in the adjustment state of the connection unit, the force generation device maintains the narrow gap between the first and second contact surfaces by applying the force of repulsion between the first and second connector parts.

6. The optical apparatus according to claim 1, wherein:

the positioning device comprises a force generation device; and

in the adjustment state of the connection unit, the force generation device maintains the narrow gap between the first and second contact surfaces by applying an action of force between the optical module and the support structure.

7. The optical apparatus according to claim 6, in the adjustment state of the connection unit, the force generation device maintains the narrow gap between the first and second contact surfaces by applying the action of force between the first and second connector parts.

8. The optical apparatus according to claim 6, wherein:

the action of force is an electromagnetic force;

a member has an electrically conducting section that can be impinged upon by electrical current; and

the member is selected from the group consisting of the optical module, the support structure and combinations thereof.

9. The optical apparatus according to claim 6, wherein:

the action of force is an electrostatic force;

a member has an electrically conducting section that can be impinged upon by electrical charge; and

the member is selected from the group consisting of the optical module, the support structure and combinations thereof.

10. The optical apparatus according to claim 6, wherein:

the action of force is a fluidic force;

at least one of the first and second connector parts comprises a feed device configured to provide a fluid in the narrow gap.

11. The optical apparatus according to claim 1, wherein:

the positioning device comprises a force generation device, a detection device and a control device connected with the force generation device and the detection device;

the detection device is configured to detect a value of a variable representative of a dimension of the narrow gap and to pass on a corresponding measurement signal to the control device,

the control device is configured to generate from the measurement signal and a setpoint value a control signal and to pass the control signal on to the force generation device, and

the force generation device is configured to generate an action of force between the first and second connector parts as a function of the control signal to maintain the narrow gap between the first and second connector parts.

12. The optical apparatus according to claim 1, wherein:

the first connector part comprises a first connector element and a second connector element;

the first connector element has a third contact surface with a third main curvature defining a third main curvature axis;

the second connector element has a fourth contact surface with a fourth main curvature defining a fourth main curvature axis;

in the installed state of the connection unit, the fourth main curvature is matched to the third main curvature and the third contact surface contacts the fourth contact surface;

the connection apparatus comprises at least part of the positioning device configured to act on the first and second connector elements;

in the adjustment state of the connection unit, a narrow gap between the third and fourth contact surfaces is maintained in a non-contact manner so that a compensating motion between the third and fourth contact surfaces about the third main curvature axis is possible without the occurrence of any action of force between the third and fourth connector parts resulting from the compensating motion.

13. The optical apparatus according to claim 12, wherein:

the positioning device comprises a force generation device; and

in the adjustment state of the connection unit, the force generation device maintains the narrow gap between the first and second contact surfaces by applying an action of force between the optical module and the support structure.

14. The optical apparatus according to claim 12, wherein:

the positioning device comprises a force generation device, a detection device and a control device connected with the force generation device and the detection device;

the detection device is configured the detect a value of a variable representative of a dimension of the second gap between the first and second connector elements and to pass on a corresponding second measurement signal to the control device;

the control device is configured to generate from the second measurement signal and a second setpoint value a second control signal and to pass the second control signal on to the force generation device; and

the force generation device is configured to generate an action of force between the first and second connector elements as a function of the second control signal to maintain the narrow gap between the first and second connector parts.

15. The optical apparatus according to claim 1, wherein:

the connection apparatus comprises a further connection unit, the further connection unit comprising a third connector part connected with the optical module and a fourth connector part connected with the support structure;

the third connector part has a third contact surface with a third main curvature defining a third main curvature axis;

the fourth connector part has a fourth contact surface with a fourth main curvature defining a fourth main curvature axis;

the fourth main curvature is matched to the third main curvature;

in the installed state of the connection unit, the third contact surface contacts the fourth contact surface in the installed state;

the connection apparatus comprises at least part of the positioning device configured to act on the third and fourth connector parts; and

in the adjustment state of the connection unit, a narrow gap between the third and fourth contact surfaces is maintained in a non-contact manner so that a compensating motion between the third and fourth contact surfaces about the third main curvature axis is possible without the occurrence of any action of force between the third and fourth connector parts resulting from the compensating motion.

16. The optical apparatus according to claim 15, wherein the positioning device is configured to substantially synchronously reduce the narrow gap between the first and second connector parts and the narrow gap between the third and fourth connector parts.

17. A method, comprising:

using a connection apparatus to connect a support structure with an optical module configured for use in microlithography, wherein;

the connection apparatus comprises a connection unit comprising a first connector part and a second connector part,

the first connector part is connected to the optical module and the second connector part is connected to the support structure,

the first connector part has a first contact surface with a first main curvature defining a first main curvature axis,

the second connector part has a second contact surface with a second main curvature defining a second main curvature axis,

the first main curvature axis matches to the second main curvature,

in an installed state, the method comprises bringing the optical module and the support structure closer to each other so that the first contact surface contacts the second contact surface in an installed state, and

in an adjustment state, the method comprises maintaining a narrow gap between the first and second contact surfaces in a non-contact manner so that a compensating motion between the first and second contact surfaces about the first main curvature axis is possible without the occurrence of any action of force between the first and second connector parts resulting from the compensating motion.

18. The method according to claim 17, comprising, applying a force of action between the optical component and the support structure to maintain the narrow gap.

19. The method according to claim 18, wherein the force of action comprises at least one force selected from the group consisting of an electrical force, a magnetic force and a fluidic force.

20. The method according to claim 17, comprising:

Detecting a value of a variable representative of a dimension of the gap between the first and second connector parts;

generating a control signal from the measurement signal and a setpoint value;

passing the control signal to a force generation device; and

using the force generation device to generate an action of force between the first and second connector parts as a function of the control signal to maintain the narrow gap generates.

21. The method according to claim 17, wherein:

the first connector part comprises a first connector element and a second connector element,

the first connector element has a third contact surface with a third main curvature defining a third main curvature axis,

the second connector element has a fourth contact with a fourth main curvature defining a fourth main curvature axis;

the fourth main curvature is matched to the third main curvature,

the method comprises bringing the optical module and the support structure closer to one another so that the third contact surface contacts the fourth contact surface in the installed state, and

in the adjustment state of the connection unit, a narrow gap between the third and fourth contact surfaces is maintained in a non-contact manner so that a second compensating motion between the third and fourth contact surfaces about the third main curvature axis is possible without the occurrence of any action of force between the first and second connector elements resulting from the second compensating motion.

22. The method according to claim 21, comprising applying an action of force between the optical module and the support structure to maintain the narrow gap between the third and fourth contact surface.

23. The method according to claim 21, comprising:

detecting a value of a variable representative of a dimension of the second gap between the first connector element and the second connector element,

passing a corresponding second measurement signal to a control device,

generating a second control signal from the second measurement signal and a second setpoint value,

passing the second control signal to the force generation device and

using the force generation device to maintain the second narrow gap generates an action of force between the optical module and the support structure as a function of the second control signal.

24. The method according to claim 17, wherein:

the connection apparatus comprises a third connector part connected to the optical module and a fourth connector part connected to the support structure,

the third connector part has a fifth contact surface with a fifth main curvature, which defines a fifth main curvature axis,

the fourth connector part has a sixth contact surface with a sixth main curvature matched to the fifth main curvature, which defines a sixth main curvature axis,

the optical module and the support structure are brought closer to one another so that the fifth contact surface contacts the sixth contact surface in the installed state,

in the adjustment state a third narrow gap between the fifth contact surface and the sixth contact surface is maintained in a non-contact manner so that a third compensating motion between the fifth contact surface and the sixth contact surface about the fifth main curvature axis is possible without the occurrence of any action of force between the third connector part and the fourth connector part resulting from the third compensating motion.

25. The method according to claim 24, wherein the narrow gap between the first connector part and the second connector part and the narrow gap between the third connector part and the fourth connector part are substantially synchronously reduced.

26. The method according to claim 24, comprising reducing the narrow gap between the first and second connector parts and the narrow gap between the third and fourth connector parts so that the first and second contact surfaces contact each other substantially simultaneously, and so that the fifth and sixth contact surfaces contact each other substantially simultaneously.

27. The method according to claim 17, wherein the optical module defines a circumferential direction and a radial direction, and the first main curvature axis runs in a direction that has at least one component in the circumferential direction and/or the radial direction.

28. The method according to claim 17, wherein at least one of the connector parts comprises a flexible decoupling section in the direction of the first main curvature axis, and the decoupling section is designed for decoupling the forces in the direction of the first main curvature axis between the optical module and the support structure.

29. The method according to claim 17, wherein the adjustment state compensating motions in at least two degrees of freedom without a force of action between the components of the connection unit resulting from the compensating motions.

30. A method, comprising:

using a connection apparatus to connect a support structure with an optical module configured to be used in microlithography, wherein;

the connection apparatus comprises a plurality of connection units,

each connection unit comprises a module connector part connected to the optical module and a structure connector part connected to the support structure,

the method comprises bringing the optical module and the support structure closer to each other so that the respective module connector part and the assigned structure connector part contact each other in an installed state,

in an adjustment state that exists prior to the installed state, a gap exists in each case between the respective module connector part and the assigned structure connector part is reduced in a non-contact manner so that the module connector parts and the assigned structure connector parts contact each other substantially simultaneously,

the method comprises detecting a value of a variable representative of a dimension of the respective gap between the module connector part and the assigned structure connector part,

the method comprises passing a corresponding measurement signal passed to a control device,

the method comprises generating from the respective measurement signal and at least one setpoint value a control signal,

the method comprises passing the control signal to a force generation device, and

the method comprises using the force generation device to generate action of force between the optical module and the support structure to achieve a predefined change in the respective gap between the module connector part and the assigned structure connector part.