Projection exposure apparatus with at least one manipulator

Patent metadata

Field	Value
Publication number	US-9846367-B2
Application number	US-201514792758-A
Country	US
Kind code	B2
Filing date	Jul 7, 2015
Priority date	Mar 29, 2012
Publication date	Dec 19, 2017
Grant date	Dec 19, 2017

Abstract

A projection exposure apparatus for microlithography includes a projection lens which includes a plurality of optical elements for imaging mask structures onto a substrate during an exposure process. The projection exposure apparatus also includes at least one manipulator configured to change, as part of a manipulator actuation, the optical effects of at least one of the optical elements within the projection lens by changing a state variable of the optical element along a predetermined travel. The projection exposure apparatus further includes an algorithm generator configured to generate a travel generating optimization algorithm, adapted to at least one predetermined imaging parameter, on the basis of the at least one predetermined imaging parameter.

First claim

What is claimed is:

1. A system, comprising:
a microlithography projection exposure apparatus, comprising:
a projection lens comprising a plurality of optical elements configured to image mask structures onto a substrate during an exposure process, the plurality of optical elements comprising a first optical element;
a manipulator configured to change a state variable of the first optical element along a predetermined travel direction; and
a first computing device in communication with the manipulator, the first computing device being programmed to establish a travel for the manipulator based on a travel algorithm; and

a second computing device arranged outside of the microlithography projection exposure apparatus, the second computing device being in communication with the first computing device, the second computing device being programmed to provide the travel algorithm to the first computing device based on information about the mask structures.

2. The system of claim 1 , wherein the information about the mask structures comprises at least one parameter selected from the group consisting of a line width, a characterization of geometric structures of the mask structures, and an orientation of mask structures.

3. The system of claim 1 , wherein the change in state variable improves an image quality of the projection lens during the exposure process.

4. The system of claim 1 , wherein the state variable of the first optical element is a positional degree of freedom of the first optical element.

5. The system of claim 1 , wherein the manipulator changes the state variable of the first optical element by an application of heat and/or coldness to the first optical element.

6. The system of claim 1 , wherein the second computing device is programmed to provide the travel algorithm to the first computing device as an algorithm configured to establish the travel for the manipulator on the basis of at least one aberration parameter which characterizes an imaging quality of the projection lens.

7. The system of claim 1 , wherein the second computing device is programmed to provide the travel algorithm to the first computing device based on a mathematical model comprising a plurality of basis functions.

8. The system of claim 1 , wherein the second computing device is programmed to provide the travel algorithm to the first computing device retrieved from a database comprising a plurality of stored algorithms.

9. The system of claim 1 , wherein the second computing device is programmed to optimize the travel algorithm to account for a change in an imaging quality of the projection lens during the exposure process.

10. The system of claim 9 , wherein the second computing device is programmed to optimize the travel algorithm to account for heating of an element during the exposure process.

11. The system of claim 9 , wherein the second computing device is programmed to optimize the travel algorithm to account for an effect of the exposure process on at least one lithographic error.

12. The system of claim 11 , wherein the at least one lithographic error comprises an overlay error.

13. The system of claim 9 , wherein the second computing device is programmed to optimize the travel algorithm based on a merit function.

14. The system of claim 1 , wherein the microlithography projection exposure apparatus comprises a sensor for measuring an external physical variable and the travel is established accounting for measurements made using the sensor.

15. The system of claim 14 , wherein the external physical variable is an air pressure.

16. A method for manipulating an optical element in a projection lens of a microlithography projection exposure apparatus, the projection lens being configured to image mask structures onto a substrate during an exposure process, the method comprising:
communicating a travel algorithm to a first computing device associated with the microlithography projection exposure apparatus, the first computing device being in communication with a manipulator and the travel algorithm being based on information about the mask structures;
establishing, using the first computing device, a travel for the manipulator based on the travel algorithm; and
changing a state variable of the first optical element along a predetermined travel direction using the manipulator based on the established travel for the manipulator.

17. The method of claim 16 , wherein the information about the mask structures comprises at least one parameter selected from the group consisting of a line width, a characterization of geometric structures of the mask structures, and an orientation of mask structures.

18. The method of claim 16 , wherein the change in state variable improves an image quality of the projection lens during the exposure process.

19. The method of claim 16 , wherein the state variable of the first optical element is a positional degree of freedom of the first optical element.

20. The method of claim 16 , wherein the manipulator changes the state variable of the first optical element by an application of heat and/or coldness to the first optical element.

21. The method of claim 16 , wherein the travel algorithm establishes the travel for the manipulator on the basis of at least one aberration parameter which characterizes an imaging quality of the projection lens.

22. The method of claim 16 , wherein the travel algorithm is optimized to account for heating of an element during the exposure process.

23. The system of claim 16 , wherein travel algorithm is optimized to account for an effect of the exposure process on at least one lithographic error.

24. The system of claim 23 , wherein the at least one lithographic error comprises an overlay error.

Assignees

• Zeiss Carl Smt Gmbh

Inventors

• Bittner Boris
• Wabra Norbert
• Hodenberg Martin Von

Classifications

• G03F7/706

  Aberration measurement · CPC title

• G03F7/70525

  Controlling normal operating mode, e.g. matching different apparatus, remote control or prediction of failure · CPC title

• G03F7/70258 Primary

  Projection system adjustments, e.g. adjustments during exposure or alignment during assembly of projection system · CPC title

• G03F7/70891

  Temperature · CPC title

• G03F7/70058

  Mask illumination systems · CPC title