Optical imaging device with thermal attenuation

Patent metadata

Field	Value
Publication number	US-9810996-B2
Application number	US-201414531109-A
Country	US
Kind code	B2
Filing date	Nov 3, 2014
Priority date	May 9, 2006
Publication date	Nov 7, 2017
Grant date	Nov 7, 2017

Abstract

An optical imaging device, in particular for use in microlithography, includes a mask device for receiving a mask having a projection pattern, a projection device with an optical element group, a substrate device for receiving a substrate and an immersion zone. The optical element group is adapted to project the projection pattern onto the substrate and includes a plurality of optical elements with an immersion element to which the substrate is at least temporarily located adjacent to during operation. During operation, the immersion zone is located between the immersion element and the substrate and is at least temporarily filled with an immersion medium. A thermal attenuation device is provided, the thermal attenuation device being adapted to reduce fluctuations within the temperature distribution of the immersion element induced by the immersion medium.

First claim

The invention claimed is:

1. An optical imaging device, comprising:
a mask device configured to receive a mask comprising a pattern;
a substrate device configured to receive a substrate;
a projection device comprising an optical element group configured to project the pattern onto the substrate, the projection device comprising a plurality of optical elements which comprise an immersion element; and
a thermal attenuation device comprising an influencing device,
wherein:
the optical imaging device comprises an immersion zone between the immersion element and the substrate;
the influencing device comprises a shielding;
during use of the optical imaging device:
the immersion element is at least temporarily located adjacent to the immersion zone; and
the immersion zone at least temporarily contains an immersion medium;
the thermal attenuation device reduces fluctuations within a temperature distribution of the immersion element induced by the immersion medium;
as a function of at least one control value, the shielding of the influencing device influences the temperature distribution of the immersion element; and
the shielding of the influencing device is disposed between a part of the immersion element and the immersion medium so that the shielding of the influencing device thermally shields the part of the immersion element against the immersion medium; and

the shielding protrudes into a projection space confined by a surface of the substrate facing the immersion element, a surface of the immersion element facing the substrate, and a projection of the immersion element onto the substrate in a direction perpendicular to the surface of the substrate.

2. The optical imaging device of claim 1 , further comprising a holding device holding the immersion element, wherein:
the thermal decoupling device comprises a first shielding, a second shielding and a third shielding;
during use of the optical imaging device:
the immersion element comprises a first area which optically used and a second area which optically unused;
the first shielding thermally shields at least a part of a first section of the second area against the immersion medium, the first section being an entire section of the second area located adjacent to the immersion medium;
the second shielding thermally shields at least a part of a second section of the second area against an adjacent section of the projection device, the second section being an entire section of the second area located adjacent to the adjacent section of the projection device; and
the third shielding thermally shields at least a part of the holding device against its environment.

3. The optical imaging device of claim 1 , further comprising a thermal decoupling device, wherein at least one of the following holds:
the thermal decoupling device is configured to at least partially thermally decouple the immersion element from at least a part of its environment;
the thermal decoupling device comprises a passive thermally insulating device;
the thermal decoupling device comprises an organic material;
the thermal decoupling device comprises an active shielding comprising a shielding element and a temperature adjustment device connected to the shielding element, the temperature adjustment device configured to maintain a selectable temperature distribution on a surface of the shielding element;
the thermal decoupling device comprises an active shielding, the temperature adjustment device configured to provide a flow of a heat carrier medium in an area of the active shielding element; and
the thermal decoupling device comprises a hydrophobic surface facing away from the immersion element;
the thermal decoupling device comprises a hydrophobic coating facing away from the immersion element.

4. The optical imaging device of claim 1 , wherein the thermal attenuation device is configured to maintain a maximum deviation from a setpoint temperature distribution for the immersion element.

5. The optical imaging device of claim 4 , wherein the maximum deviation is less than 10 milliKelvin.

6. The optical imaging device of claim 1 , wherein:
the immersion element has an actual temperature distribution;
the immersion medium has a setpoint temperature distribution;
the thermal attenuation device further comprises an establishing device and a control device;
the control device is at least temporarily connected to both the establishing device and the influencing device;
the establishing device establishes a parameter that influences the actual temperature distribution or that is representative of the actual temperature distribution;
the control device is configured to establish the control value as a function of the parameter and the setpoint temperature distribution;
the influencing device is configured to influence a control parameter as a function of the at least one established control value; and
the control parameter influences the actual temperature distribution to counteract a deviation of the actual temperature distribution from the setpoint temperature distribution.

7. The optical imaging device of claim 6 , wherein the parameter comprises a parameter selected from the group consisting of a local temperature of the immersion medium and a local temperature of the immersion element.

8. The optical imaging device of claim 7 , wherein the establishing device comprises a device configured to: a) measure the local temperature; and/or b) estimate the local temperature.

9. The optical imaging device of claim 6 , wherein the control parameter is selected from the group consisting of a temperature of the immersion medium, a flow rate of the immersion medium, a temperature of a gas atmosphere contacting the immersion medium, a humidity of a gas atmosphere contacting the immersion medium, a flow rate of a gas atmosphere contacting the immersion medium, and a temperature of an temperature adjustment element operatively connected to the immersion element.

10. The optical imaging device of claim 1 , further comprising a control device configured to use a model to establish the control value, the model comprising a model selected from the group consisting of a temperature behavior model of the immersion element and a temperature behavior model of the immersion medium within the immersion zone for establishing the control value.

11. The optical imaging device according claim 10 , wherein:
the control device comprises a memory to store data representing the model or parameters to calculate model data representing the model; and
during use of the optical imaging device, the control device uses the model data to establish the control value.

12. The optical imaging device of claim 1 , wherein the influencing device comprises a temperature adjustment device configured to adjust the temperature of the immersion medium during use of the optical imaging device.

13. The optical imaging device of claim 12 , further comprising a control device, wherein during use of the optical imaging device:
the control device establishes the control value for the temperature adjustment device as a function of an alteration of a temperature distribution expected within the immersion medium so that the temperature adjustment device adjusts the temperature of the immersion medium supplied to the immersion zone to a supply temperature; and
the supply temperature is selected so that, due to the alteration of the temperature distribution to be expected within the immersion medium, a given temperature distribution is to be expected within the immersion medium.

14. The optical imaging device of claim 12 , wherein the tem

Assignees

• Zeiss Carl Smt Gmbh

Inventors

• Gellrich Bernhard
• Kugler Jens
• Ittner Thomas
• Hembacher Stefan
• Schimitzek Karl-Heinz
• Tayebati Payam
• Holderer Hubert

Classifications

• G03F7/70891

  Temperature · CPC title

• G03F7/7085

  Detection arrangement, e.g. detectors of apparatus alignment possibly mounted on wafers, exposure dose, photo-cleaning flux, stray light, thermal load · CPC title

• G03F7/2041

  in the presence of a fluid, e.g. immersion; using fluid cooling means · CPC title

• G03F7/70341 Primary

  Details of immersion lithography aspects, e.g. exposure media or control of immersion liquid supply (chemical composition of immersion liquids G03F7/2041) · CPC title

• H10P72/0602

  Temperature monitoring · CPC title