Interference systems for microlithgraphic projection exposure systems
View Patent ↗An optical system of a microlithographic projection exposure apparatus permits comparatively flexible and fast influencing of the intensity distribution and/or the polarization state. The optical system includes at least one layer system that is at least one-side bounded by a lens or a mirror. The layer system is an interference layer system of several layers and has at least one liquid or gaseous layer portion with a maximum thickness of one micrometer (μm), and a manipulator for manipulation of the thickness profile of the layer portion.
1. An article, comprising:
an optical element selected from the group consisting of a lens and a mirror; and
an interference layer system bounded by the optical element,
wherein the interference layer system comprises a plurality of layers including a first layer comprising a liquid or a gas, a maximum thickness of the first layer is at most one micrometer, and a thickness profile of the first layer is manipulatable, and
wherein, during use of the article in a microlithographic projection exposure apparatus, the thickness profile of the first layer is adjustable in dependence on a polarization distribution currently measured in a predetermined plane of the projection exposure apparatus.
2. An article as set forth in claim 1 , wherein the maximum thickness of the first layer is at most 500 nanometers.
3. An article as set forth in claim 1 , wherein the maximum thickness of the first layer is at most half of a working wavelength of the optical system.
4. An article as set forth in claim 1 , wherein the maximum thickness of the first layer is in the range of between 10 nm and 100 nm.
5. An article as set forth in claim 1 , wherein the first layer comprises water or at least one gas selected from the group consisting of air, nitrogen (N 2 ), argon (Ar), and helium (He).
6. An article as set forth in claim 1 , wherein the optical element is a mirror, the manipulator comprises an arrangement of actuators that is provided on a surface of the mirror, and the surface of the mirror not being optically effective.
7. An article as set forth in claim 1 , wherein the optical element is a lens, and the manipulator comprises an arrangement of actuators provided at an edge of the lens.
8. An article as set forth in claim 1 , wherein the interference layer system comprises an alternate succession of layers comprising a first material and layers comprising a second material, wherein the first material has a refractive index that is smaller than a refractive index of quartz glass (SiO 2 ) at a working wavelength of the optical system, and the second material has a refractive index that is greater than the refractive index of quartz glass (SiO 2 ) at the working wavelength.
9. An apparatus, comprising:
an illumination system; and
a projection objective,
wherein at least one member selected from the group consisting of the illumination system and the projection objective comprises:
an optical element selected from the group consisting of a lens and a mirror;
an interference layer system bounded by the optical element, the interference layer system comprising a plurality of layers including a first layer having a maximum thickness of at most one micrometer, the first layer comprising a liquid or a gas; and
a manipulator configured to manipulate a thickness profile of the first layer,
wherein the apparatus is a microlithographic projection exposure apparatus, and
wherein, during use of the apparatus, manipulation of the thickness profile of the first layer is adjustable in dependence on a polarization distribution currently measured in a predetermined plane of the apparatus.
10. An apparatus as set forth in claim 9 , wherein the maximum thickness of the first layer is at most 500 nanometers.
11. An apparatus as set forth in claim 9 , wherein the maximum thickness of the first layer is at most half of a working wavelength of the optical system.
12. An apparatus as set forth in claim 9 , wherein the maximum thickness of the first layer is in the range of between 10 nm and 100 nm.
13. An apparatus as set forth in claim 9 , wherein the interference layer system comprises an alternate succession of layers comprising a first material and layers comprising a second material, wherein the first material has a refractive index that is smaller than a refractive index of quartz glass (SiO 2 ) at a working wavelength of the optical system, and the second material has a refractive index that is greater than the refractive index of quartz glass (SiO 2 ) at the working wavelength.
14. An apparatus as set forth in claim 9 , wherein the first layer comprises water or at least one gas selected from the group consisting of air, nitrogen (N 2 ), argon (Ar), and helium (He).
15. An apparatus as set forth in claim 9 , wherein the optical element is a mirror, the manipulator comprises an arrangement of actuators that is provided on a surface of the mirror, and the surface of the mirror not being optically effective.
16. An apparatus as set forth in claim 9 , wherein the optical element is a lens, and the manipulator comprises an arrangement of actuators provided at an edge of the lens.
17. An optical system, comprising:
an optical element selected from the group consisting of a lens and a mirror;
an interference layer system bounded by the optical element, the interference layer system comprising a plurality of layers including a first layer having a maximum thickness of at most one micrometer, the first layer comprising a liquid or a gas; and
a manipulator configured to manipulate a thickness profile of the first layer,
wherein the optical system is configured to be used in a microlithographic projection exposure apparatus; and
wherein, during use of the optical system, manipulation of the thickness profile of the first layer is adjustable in dependence on a polarization distribution currently measured in a predetermined plane of the optical system.
18. An optical system as set forth in claim 17 , wherein the maximum thickness of the first layer is at most 500 nanometers.
19. An optical system as set forth in claim 17 , wherein the maximum thickness of the first layer is at most half of a working wavelength of the optical system.
20. An optical system as set forth in claim 17 , wherein the maximum thickness of the first layer is in the range of between 10 nm and 100 nm.
21. An optical system as set forth in claim 17 , wherein the interference layer system comprises an alternate succession of layers comprising a first material and layers comprising a second material, wherein the first material has a refractive index that is smaller than a refractive index of quartz glass (SiO 2 ) at a working wavelength of the optical system, and the second material has a refractive index that is greater than the refractive index of quartz glass (SiO 2 ) at the working wavelength.
22. An optical system as set forth in claim 17 , wherein the first layer comprises water or at least one gas selected from the group consisting of air, nitrogen (N2), argon (Ar), and helium (He).
23. An optical system as set forth in claim 17 , wherein the optical element is a mirror, the manipulator comprises an arrangement of actuators that is provided on a surface of the mirror, and the surface of the mirror not being optically effective.
24. An optical system as set forth in claim 17 , wherein the optical element is a lens, and the manipulator comprises an arrangement of actuators provided at an edge of the lens.