Photon sieve for optical systems in micro-lithography

• US 20070194254A1
• Filed: 02/17/2006
• Published: 08/23/2007
• Est. Priority Date: 02/17/2006
• Status: Active Grant

• Current Assignee: ASML Netherlands BV (ASML Holding NV)
• Original Assignee: ASML Netherlands BV (ASML Holding NV)
• Inventors: Hubertus Mulkens, Johannes
• Granted Patent: US 7,368,744 B2
• Time in Patent Office: Days
• US Class Current: 250/504.00R
• CPC Class Codes: G03F 7/70091 Illumination settings, i.e. intensity distribution in the pupil plane or angular distribution in the field plane; On-axis or off-axis settings, e.g. annular, dipole or quadrupole settings; Partial coherence control, i.e. sigma or numerical aperture [NA]
• CPC Class Codes: G03F 7/70108 Off-axis setting using a light-guiding element, e.g. diffractive optical elements [DOEs] or light guides
• CPC Class Codes: G03F 7/70158 Diffractive optical elements
• CPC Class Codes: G03F 7/70191 Optical correction elements, filters or phase plates for controlling intensity, wavelength, polarisation, phase or the like
• CPC Class Codes: G03F 7/7025 Size or form of projection system aperture, e.g. aperture stops, diaphragms or pupil obscuration; Control thereof
• CPC Class Codes: G03F 7/70308 Optical correction elements, filters or phase plates for manipulating imaging light, e.g. intensity, wavelength, polarisation, phase or image shift
• CPC Class Codes: G03F 7/70575 Wavelength control, e.g. control of bandwidth, multiple wavelength, selection of wavelength or matching of optical components to wavelength

Abstract

The use of photon sieves may be as a pupil defining element in an illumination system; a field of defining elements in an illumination system; a pupil lens element in a projection lens; a color correction system in the projection system; or as a transmitting diffractive element for EUV.

Claims

1. A lithographic apparatus, comprising:

an illumination system configured to condition a radiation beam; and

a patterning device configured to modulate the cross-section of the radiation beam, wherein a pupil-defining element in the illumination system comprises a photon sieve.

6. A lithographic apparatus according to claim 1, wherein the photon sieve comprises a number of holes such that transmission of the radiation beam is between 30 and 70%.

10. A lithographic apparatus according td claim 1, wherein the photon sieve comprises holes in concentric circular zones.

11. A lithographic apparatus according to claim 10, wherein the photon sieve comprises two different overlapping patterns of circular zones.

18. A lithographic apparatus according to claim 1, wherein the photon sieve comprises holes positioned such that the optical path length from an illumination system source to the focal point of the photon sieve is a whole number of wavelengths of the radiation beam.

22. A lithographic apparatus according to claim 1, wherein the photon sieve is made of metal foil and holes in the photon sieve are etched or laser beam drilled.

2. A lithographic apparatus, comprising:

an illumination system configured to condition a radiation beam;

a patterning device configured to modulate the cross-section of the radiation beam, wherein a field-defining element in the illumination system comprises a photon sieve.

7. A lithographic apparatus according to claim 2, wherein the photon sieve comprises a number of holes such that transmission of the radiation beam is at least 50%.

12. A lithographic apparatus according to claim 2, wherein the photon sieve comprises holes in concentric circular zones.

13. A lithographic apparatus according to claim 12, wherein the photon sieve comprises two different overlapping patterns of circular zones of holes.

19. A lithographic apparatus according to claim 2, wherein the photon sieve comprises holes positioned such that the optical path length from an illumination system source to the focal point of the photon sieve is a whole number of wavelengths of the radiation beam.

23. A lithographic apparatus according to claim 2, wherein the photon sieve is made of metal foil and holes in the photon sieve are etched or laser beam drilled.

3. A lithographic apparatus, comprising:

an illumination system configured to condition a radiation beam;

a patterning device configured to modulate the cross-section of the radiation beam; and

a projection system, comprising a pupil lens element, configured to project the modulated radiation beam onto a target portion of a substrate, wherein the pupil lens element in the projection system comprises a photon sieve.

5. A lithographic apparatus according to claim 3, wherein the pupil lens element has positive dispersion and is combined with a lens with negative dispersion for color correction of the radiation beam.

8. A lithographic apparatus according to claim 3, wherein the photon sieve comprises a number of holes such that transmission of the radiation beam is at least 50%.

14. A lithographic apparatus according to claim 3, wherein the photon sieve comprises holes in concentric circular zones.

15. A lithographic apparatus according to claim 14, wherein the photon sieve comprises two different overlapping patterns of circular zones of holes.

17. A lithographic apparatus according to claim 15, wherein the photon sieve comprises two different overlapping patterns of circular zones of holes.

20. A lithographic apparatus according to claim 3, wherein the photon sieve comprises holes positioned such that the optical path length from an illumination system source to the focal point of the photon sieve is a whole number of wavelengths of the radiation beam.

24. A lithographic apparatus according to claim 3, wherein the photon sieve is made of metal foil and holes in the photon sieve are etched or laser beam drilled.

4. A lithographic apparatus, comprising:

an illumination system configured to condition an EUV radiation beam;

a patterning device configured to modulate the cross-section of the EUV radiation beam; and

a projection system, comprising a pupil lens element, configured to project the modulated radiation beam onto a target portion of a substrate, wherein the illumination system or the projection system comprises mirror optics and a photon sieve.

9. A lithographic apparatus according to claim 4, wherein the photon sieve comprises a number of holes such that transmission of the radiation beam is at least 50%.

16. A lithographic apparatus according to claim 4, wherein the photon sieve comprises holes in concentric circular zones.

21. A lithographic apparatus according to claim 4, wherein the photon sieve comprises holes positioned such that the optical path length from an illumination system source to the focal point of the photon sieve is a whole number of wavelengths of the radiation beam.

25. A lithographic apparatus according to claim 4, wherein the photon sieve is made of metal foil and holes in the photon sieve are etched or laser beam drilled.

26. A device manufacturing method comprising projecting a modulated beam of radiation onto a substrate, wherein the radiation is diffracted in an illumination system using a photon sieve.

27. A device manufacturing method comprising projecting a modulated beam of radiation onto a substrate, wherein the radiation is patterned using a patterning device and focused in a projection system using a photon sieve.