Advanced illumination system for use in microlithography

1. A system for microlithography comprising:

an illumination source;

an illumination optical system including, in order from an objective side:

(a) a first diffractive optical element that receives illumination from the illumination source;

(b) a non-imaging zoom lens;

(c) a second diffractive optical element;

(d) a condenser lens;

(e) a relay lens;

(f) a reticle; and

a projection optical system that images the reticle onto a substrate,

wherein the system for microlithography provides a zoomable numerical aperture, and

wherein a ratio of a numerical aperture of the illumination system and a numerical aperture of the projection optical system is variable between about 0.2 and 0.4.

2. The system of claim 1 , wherein a field size of the system is discretely variable.

3. The system of claim 1 , wherein a field size of the system is discretely variable and the ratio is continuously variable.

4. The system of claim 1 , wherein a field size of the system is continuously variable.

5. The system of claim 1 , further comprising a third diffractive optical element between the second diffractive optical element and the condenser lens.

6. The system of claim 5 , wherein a position of the third diffractive optical element is adjustable to continuously adjust a field size of the system.

7. The system of claim 1 , wherein the ratio is continuously variable.

8. The system of claim 1 , wherein the first diffractive optical element comprises a microlense array.

9. The system of claim 1 , wherein the first diffractive optical element comprises a Fresnel lens.

10. The system of claim 1 , wherein the first diffractive optical element comprises a diffraction grating.

11. The system of claim 1 , wherein the illumination system further comprises an axicon between the zoom lens and the second diffractive element.

12. The system of claim 1 , wherein the illumination system further comprises an axicon between the second diffractive element and the condenser lens.

13. The system of claim 1 , wherein the second diffractive optical element has a rectangular numerical aperture.

14. The system of claim 1 , wherein the illumination system further comprises a telecentric stop centered in the relay lens.

15. A system for microlithography comprising:

an illumination source;

an illumination optical system that receives illumination from the illumination source; and

a projection optical system that receives illumination from the illumination system,

wherein a ratio of a numerical aperture of the illumination system and a numerical aperture of the projection optical system is variable between about 0.2 and 0.4 while a field size is discretely variable.

16. The system of claim 15 , wherein the illumination system further comprises a first diffractive optical element that receives illumination from the illumination source.

17. The system of claim 15 , wherein the first diffractive optical element includes a Fresnel lens.

18. The system of claim 15 , wherein the illumination system further comprises a non-imaging zoom lens that receives illumination from the first diffractive element.

19. The system of claim 18 , wherein the illumination system further includes an axicon that receives illumination from the zoom lens.

20. The system of claim 15 , wherein the illumination system is a whole field illumination system.

21. An illumination system for microlithography comprising, in order from an objective side:

a first diffractive optical element;

a non-imaging zoom lens;

a second diffractive optical element having a rectangular numerical aperture;

a condenser lens;

a relay lens; and

a projection optical system, wherein a field size of the system and a partial coherence of the system are both variable, and wherein the partial coherence of the system is continuously variable between about 0.2 and 0.4.

22. The system of claim 21 , wherein a field size of the illumination system is discretely variable.

23. The system of claim 21 , wherein the illumination system further comprises an axicon between the non-imaging zoom lens and the second diffractive element.

24. The system of claim 21 , wherein the illumination system further comprises and axicon between the second diffractive optical element and the non-imaging zoom lens.

25. A system for microlithography comprising:

an illumination system including, in order from an objective side:

(a) a zoom lens having a first diffractive optical element on a first side, and a second diffractive optical element on a second side;

(b) a condenser lens;

(c) a relay lens; and

a projection optical system,

wherein a partial coherence of the system for microlithography is variable between about 0.2 and 0.4.

26. The system of claim 25 , wherein a field size of the system for microlithography is discretely adjustable.

27. The system of claim 25 , wherein a field size of the system for microlithography is continuously adjustable.

28. The system of claim 25 , wherein the zoom lens is a non-imaging zoom lens.

29. The system of claim 25 , wherein the illumination system further comprises an axicon between the zoom lens and the condenser lens.

30. The system of claim 25 , wherein the illumination system is a whole field system.