Claims
- 1. A projection optical system that projects an image of an object in an object surface onto an image surface with a reduction magnification comprising, in light path order from said object surface:
- a first group of lenses with positive refractive power, said first group of lenses comprising at least two positive lenses;
- a second group of lenses forming an approximately afocal system, said second group of lenses comprising, in light path order from said object surface,
- a first subgroup of lenses with negative refractive power, said first subgroup of lenses comprising at least two negative lenses,
- a second subgroup of lenses with positive refractive power, said second subgroup of lenses comprising at least four positive lenses,
- a third subgroup of lenses with negative refractive power, said third subgroup of lenses comprising at least two negative lenses, and
- a fourth subgroup of lenses with positive refractive power, said fourth subgroup of lenses comprising at least two positive lenses; and
- a third group of lenses with positive refractive power, said third group of lenses comprising at least two positive lenses;
- wherein:
- said projection optical system has a focal length F,
- said projection optical system has a projection magnification B,
- said object surface and said image surface are separated by a distance L,
- a lens surface in said first group of lenses that is closest to said object surface is separated from said object surface by a distance d.sub.0,
- said first group of lenses has a focal length f.sub.1,
- said third group of lenses has a focal length f.sub.3,
- 1.8.ltoreq..vertline.F/(B.multidot.L).vertline.,
- d.sub.0 /L.ltoreq.0.2, and
- 0.80.ltoreq..vertline.f.sub.3 /f.sub.1 .vertline..ltoreq.1.5.
- 2. The projection optical system of claim 1, wherein:
- said first group of lenses has a focal length f.sub.1 ; and
- 0.05.ltoreq.f.sub.1 /L.ltoreq.0.3.
- 3. The projection optical system of claim 2, wherein:
- a maximum height of the object from the optical axis of said projection optical system on said object surface is represented by H.sub.MAX ; and
- 0.04.ltoreq.H.sub.MAX /L.ltoreq.0.2.
- 4. The projection optical system of claim 1, wherein:
- said first subgroup of lenses has a focal length f.sub.21 ;
- said second subgroup of lenses has a focal length f.sub.22 ; and
- 1.5.ltoreq..vertline.f.sub.22 /f.sub.21 .vertline..ltoreq.5.
- 5. The projection optical system of claim 4, wherein:
- said third subgroup of lenses has a focal length f.sub.23 ; and
- 0.02.ltoreq..vertline.f.sub.23 /L.vertline..ltoreq.0.10.
- 6. The projection optical system of claim 1, wherein:
- said first subgroup of lenses has a focal length f.sub.21 ;
- said second subgroup of lenses has a focal length f.sub.22 ; and
- 1.7.ltoreq..vertline.f.sub.22 /f.sub.21 .vertline..ltoreq.5.
- 7. The projection optical system of claim 1, wherein said second subgroup of lenses comprises two biconvex lenses.
- 8. The projection optical system of claim 6, wherein:
- the paraxial marginal ray from the axial object point on said object surface enters said first group of lenses at an angle of incidence u.sub.1 ;
- the paraxial marginal ray from the axial object point on said object surface enters said second group of lenses at an angle of incidence u.sub.2 ;
- the paraxial marginal ray from the axial object point on said object surface emerges from said second group of lenses at an angle of emergence u.sub.2 ';
- the paraxial marginal ray from the axial object point on said object surface emerges from said third group of lenses at an angle of emergence u.sub.3 ';
- .vertline.u.sub.2 /u.sub.1 .vertline..ltoreq.0.5; and
- .vertline.u.sub.2 '/u.sub.3 '.vertline..ltoreq.0.5.
- 9. The projection optical system of claim 8, wherein:
- said second group of lenses has a focal length f.sub.2 ;
- said third group of lenses has a focal length f.sub.3 ;
- .vertline.f.sub.2 .vertline.>f.sub.1 ; and
- .vertline.f.sub.2 .vertline.>f.sub.3.
- 10. The projection optical system of claim 3, wherein:
- said first subgroup of lenses has a focal length f.sub.21 ;
- said second subgroup of lenses has a focal length f.sub.22 ; and
- 1.5.ltoreq..vertline.f.sub.22 /f.sub.21 .vertline..ltoreq.5.
- 11. The projection optical system of claim 10, wherein:
- said third group of lenses has a focal length f.sub.23 ; and
- 0. 02.ltoreq..vertline.f.sub.23 /L.vertline..ltoreq.0.10.
- 12. The projection optical system of claim 11, wherein 1.7.ltoreq..vertline.f.sub.22 /f.sub.21 .vertline..ltoreq.5.
- 13. An exposure method for exposing a predetermined pattern formed on a mask onto a substrate by using the projection optical system according to claim 1, the method comprising the steps of:
- illuminating the mask in said object surface with light of a predetermined exposure wavelength; and
- projecting an image of said pattern formed on said mask onto said substrate in said image surface through said projection optical system.
- 14. The exposure method of claim 13 wherein said predetermined pattern formed on said mask is an integrated circuit pattern.
- 15. An exposure method for exposing a predetermined pattern formed on a mask onto a substrate by using the projection optical system according to claim 5, the method comprising the steps of:
- illuminating the mask in said object surface with light of a predetermined exposure wavelength; and
- projecting an image of said pattern formed on said mask onto said substrate in said image surface through said projection optical system.
- 16. The exposure method of claim 15 wherein said predetermined pattern formed on said mask is an integrated circuit pattern.
- 17. An exposure method for exposing a predetermined pattern formed on a mask onto a substrate by using the projection optical system according to claim 9, the method comprising the steps of:
- illuminating the mask in said object surface with light of a predetermined exposure wavelength; and
- projecting an image of said pattern formed on said mask onto said substrate in said image surface through said projection optical system.
- 18. The exposure method of claim 17 wherein said predetermined pattern formed on said mask is an integrated circuit pattern.
- 19. An exposure method for exposing a predetermined pattern formed on a mask onto a substrate by using the projection optical system according to claim 12, the method comprising the steps of:
- illuminating the mask in said object surface with light of a predetermined exposure wavelength; and
- projecting an image of said pattern formed on said mask onto said substrate in said image surface through said projection optical system.
- 20. The exposure method of claim 19 wherein said predetermined pattern formed on said mask is an integrated circuit pattern.
- 21. A projection optical system that projects an image of an object in an object surface onto an image surface with a reduction magnification comprising, in light path order from said object surface:
- a first group of lenses with positive refractive power, said first group of lenses comprising at least two positive lenses;
- a second group of lenses forming an approximately afocal system, said second group of lenses comprising, in light path order from said object surface,
- a first subgroup of lenses with negative refractive power, said first subgroup of lenses comprising at least two negative lenses,
- a second subgroup of lenses with positive refractive power, said second subgroup of lenses comprising at least four positive lenses, and
- a third subgroup of lenses with negative refractive power, said third subgroup of lenses comprising at least two negative lenses; and
- a third group of lenses with positive refractive power, said third group of lenses comprising at least two positive lenses;
- wherein:
- said projection optical system has a focal length F,
- said projection optical system has a projection magnification B,
- said object surface and said image surface are separated by a distance L,
- a lens surface in said first group of lenses that is closest to said object surface is separated from said object surface by a distance d.sub.0,
- said first group of lenses has a focal length f.sub.1,
- said third group of lenses has a focal length f.sub.3,
- 1.8.ltoreq..vertline.F/(B.multidot.L).vertline..ltoreq.6,
- d.sub.0 /L.ltoreq.0.2, and
- 0.80.ltoreq..vertline.f.sub.3 /f.sub.1 .vertline..ltoreq.1.5.
- 22. The projection optical system of claim 21, wherein:
- said first group of lenses has a focal length f.sub.1 ;
- said third group of lenses has a focal length f.sub.3 ; and
- 0.8.ltoreq.f.sub.3 /f.sub.1 .ltoreq.1.2.
- 23. The projection optical system of claim 21, wherein said first subgroup of lenses comprises:
- a negative lens with its stronger curvature facing the image surface side;
- a negative biconcave lens; and
- a negative lens with its stronger curvature facing the object surface side.
- 24. The projection optical system of claim 23, wherein said second subgroup of lenses comprises:
- a positive lens with its stronger curvature facing the image surface side;
- at least two positive biconvex lenses; and a
- positive lens with its stronger curvature facing said object surface side.
- 25. The projection optical system of claim 24, wherein said third subgroup of lenses comprises:
- a negative lens with its stronger curvature facing the image surface side;
- a negative biconcave lens; and
- a negative lens with its stronger curvature facing the object surface side.
- 26. The projection optical system of claim 25, wherein:
- said second group of lenses further comprises, on the image surface side of said third subgroup of lenses, a fourth subgroup of lenses with positive refractive power; and
- said fourth subgroup of lenses comprises at least two positive lenses with their convex surfaces facing the image surface side.
- 27. The projection optical system of claim 26, wherein said first group of lenses comprises:
- a positive lens with its stronger curvature facing the image surface side; and
- a positive biconvex lens.
- 28. The projection optical system of claim 27, wherein said third group of lenses comprises at least three positive lenses with their convex surfaces facing the object surface side.
- 29. The projection optical system of claim 21, wherein said second group of lenses has weak positive refractive power.
- 30. The projection optical system of claim 21, wherein:
- said first group of lenses has a focal length f.sub.1 ; and
- 0.05.ltoreq.f.sub.1 /L.ltoreq.0.3.
- 31. The projection optical system of claim 30, wherein:
- said first subgroup of lenses has a focal length f.sub.21 ;
- said second subgroup of lenses has a focal length f22; and
- 1.5.ltoreq..vertline.f.sub.22 /f.sub.21 .vertline..ltoreq.5.
- 32. The projection optical system of claim 31, wherein:
- said third subgroup of lenses has a focal length f.sub.23 ; and
- 0.02.ltoreq..vertline.f.sub.23 /L.vertline..ltoreq.0.10.
- 33. The projection optical system of claim 32, wherein:
- the paraxial marginal ray from the axial object point on said object surface enters said first group of lenses at an angle of incidence u.sub.1 ;
- the paraxial marginal ray from the axial object point on said object surface enters said second group of lenses at an angle of incidence u.sub.2 ;
- the paraxial marginal ray from the axial object point on said object surface emerges from said second group of lenses at an angle of emergence u.sub.2 ';
- the paraxial marginal ray from the axial object point on said object surface emerges from said third group of lenses at an angle of emergence u.sub.3 ';
- .vertline.u.sub.2 /u.sub.1 .vertline..ltoreq.0.5; and
- .vertline.u.sub.2 '/u.sub.3 '.vertline..ltoreq.0.5.
- 34. The projection optical system of claim 33, wherein:
- said second group of lenses has a focal length f.sub.2 ;
- said third group of lenses has a focal length f.sub.3 ;
- .vertline.f.sub.2 .vertline.>f.sub.1 ; and
- .vertline.f.sub.2 .vertline.>f.sub.3.
- 35. An exposure method for exposing a predetermined pattern formed on a mask onto a substrate by using the projection optical system according to claim 31, the method comprising the steps of:
- illuminating the mask in said object surface with light of a predetermined exposure wavelength; and
- projecting an image of said pattern formed on said mask onto said substrate in said image surface through said projection optical system.
- 36. The exposure method of claim 35 wherein said predetermined pattern formed on said mask is an integrated circuit pattern.
- 37. An exposure method for exposing a predetermined pattern formed on a mask onto a substrate by using the projection optical system according to claim 21, the method comprising the steps of:
- illuminating the mask in said object surface with light of a predetermined exposure wavelength; and
- projecting an image of said pattern formed on said mask onto said substrate in said image surface through said projection optical system.
- 38. The exposure method of claim 37 wherein said predetermined pattern formed on said mask is an integrated circuit pattern.
- 39. An exposure method for exposing a predetermined pattern formed on a mask onto a substrate by using the projection optical system according to claim 26, the method comprising the steps of:
- illuminating the mask in said object surface with light of a predetermined exposure wavelength; and
- projecting an image of said pattern formed on said mask onto said substrate in said image surface through said projection optical system.
- 40. The exposure method of claim 39 wherein said predetermined pattern formed on said mask is an integrated circuit pattern.
- 41. A projection aligner comprising:
- an illumination system that illuminates a first object having an object surface on which a pattern is formed;
- a projection optical system which projects an image of said pattern onto an image surface on a second object;
- a first supporting unit that supports said first object;
- a second supporting unit that supports said second object; and
- said projection optical system comprising, in light path order from said object surface:
- a first group of lenses with positive refractive power, said first group of lenses comprising at least two positive lenses;
- a second group of lenses forming an approximately afocal system, said second group of lenses comprising, in light path order from said object surface,
- a first subgroup of lenses with negative refractive power, said first subgroup of lenses comprising at least two negative lenses,
- a second subgroup of lenses with positive refractive power, said second subgroup of lenses comprising at least four positive lenses,
- a third subgroup of lenses with negative refractive power, said third subgroup of lenses comprising at least two negative lenses, and
- a fourth subgroup of lenses with positive refractive power, said fourth subgroup of lenses comprising at least two positive lenses; and
- a third group of lenses with positive refractive power, said third group of lenses comprising at least two positive lenses;
- wherein:
- said projection optical system has a focal length F,
- said projection optical system has a projection magnification B,
- said object surface and said image surface are separated by a distance L,
- a lens surface in said first group of lenses that is closest to said object surface is separated from said object surface by a distance d.sub.0,
- said first group of lenses has a focal length f.sub.1,
- said third group of lenses has a focal length f.sub.3,
- 1.8.ltoreq..vertline.F/(B.multidot.L).vertline.,
- d.sub.0 /L.ltoreq.0.2, and
- 0.80.ltoreq..vertline.f.sub.3 /f.sub.1 .vertline..ltoreq.1.5.
- 42. The projection aligner of claim 41, wherein said first subgroup of lenses comprises:
- a negative lens with its stronger curvature facing the image surface side;
- a negative biconcave lens; and
- a negative lens with its stronger curvature facing the object surface side.
- 43. The projection aligner of claim 41, wherein the second subgroup of lenses comprises:
- a positive lens with its stronger curvature facing the object surface side;
- at least two positive biconvex lenses; and
- a positive lens with its stronger curvature facing the image surface side.
- 44. The projection aligner of claim 41, wherein said third subgroup of lenses comprises:
- a negative lens with its stronger curvature facing the image surface side;
- a negative biconcave lens; and a negative lens with its stronger curvature facing the object surface side.
- 45. The projection aligner of claim 41, wherein:
- said at least two positive lenses in said fourth subgroup of lenses have convex surfaces facing the image surface side.
- 46. A projection aligner comprising:
- an illumination system that illuminates a first object having an object surface on which a pattern is formed;
- a projection optical system which projects an image of said pattern onto an image surface on a second object;
- a first supporting unit that supports said first object;
- a second supporting unit that supports said second object; and
- said projection optical system comprising, in light path order from said object surface:
- a first group of lenses with positive refractive power, said first group of lenses comprising at least two positive lenses;
- a second group of lenses forming an approximately afocal system, said second group of lenses comprising, in light path order from said object surface,
- a first subgroup of lenses with negative refractive power, said first subgroup of lenses comprising at least two negative lenses,
- a second subgroup of lenses with positive refractive power, said second subgroup of lenses comprising at least four positive lenses, and
- a third subgroup of lenses with negative refractive power, said third subgroup of lenses comprising at least two negative lenses; and
- a third group of lenses with positive refractive power, said third group of lenses comprising at least two positive lenses;
- wherein:
- said projection optical system has a focal length F,
- said projection optical system has a projection magnification B,
- said object surface and said image surface are separated by a distance L,
- a lens surface in said first group of lenses that is closest to said object surface is separated from said object surface by a distance d0,
- said first group of lenses has a focal length f1,
- said third group of lenses has a focal length f3,
- 1. 8.ltoreq..vertline.F/(B.multidot.L).vertline..ltoreq.6,
- d.sub.0 /L.ltoreq.0.2, and
- 0.80.ltoreq..vertline.f.sub.3 /f.sub.1 .ltoreq.1.5.
- 47. The projection aligner of claim 46, wherein said second group of lenses further comprises, on the image surface side of said third subgroup of lenses, a fourth subgroup of lenses having positive refractive power.
- 48. The projection aligner of claim 47, wherein:
- said fourth subgroup of lenses comprises at least two positive lenses.
Parent Case Info
This is a Continuation of application Ser. No. 08/727,206 filed Apr. 30, 1996, now abandoned, which is a Continuation of application Ser. No. 08/152,490 filed Nov. 15, 1993, now abandoned.
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Continuations (2)
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Number |
Date |
Country |
Parent |
727206 |
Apr 1996 |
|
Parent |
152490 |
Nov 1993 |
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