Projection optical system and exposure apparatus and method

A projection optical system capable of forming an image of a pattern of an object onto a workpiece over an exposure field, said system comprising objectwise to imagewise along an optical axis:

• a) a first lens group having positive refractive power and including a lens subgroup G1p surrounded imagewise by a first negative lens having surfaces and objectwise by a second negative lens having surfaces;
• b) a second lens group having negative refractive power and including a lens subgroup G2n surrounded imagewise by a first positive lens having surfaces and objectwise by a second positive lens having surfaces;
• c) a third lens group having positive refractive power and including at least one negative lens;
• d) a fourth lens group having negative refractive power and including a lens subgroup G4n with at least three negative lenses;
• e) a fifth lens group having positive refractive power and having at least two negative lenses and including a lens subgroup G5p with at least four positive lenses;
• wherein said system further includes:
• f) an aperture stop, located between said lenses in said fifth lens group, for determining the numerical aperture of the projection optical system;
• and
• g) a position Q where a paraxial principal ray intersects the optical axis, wherein said paraxial principal ray corresponds to a ray from the workpiece side impinging upon said projection optical system parallel to the optical axis;
• and
• h) wherein said system satisfies one or more of the conditions:
• 0.05<f1/L<0.4 (1)
• 0.025<−f2/L<0.15 (2)
• 0.08<f3/L<0.35 (3)
• 0.04<−f4/L<0.16 (4)
• 0.06<f5/L<0.35 (5)
• 0.005<dQ/{L×(1−NA)}<0.2 (6)
• wherein L is the distance along the optical axis from the object to the workpiece, f1 is the focal length of said subgroup G1p, f2 is the focal length of said subgroup G2n, f3 is the focal length of said third lens group, f4 is the focal length of said subgroup G4n, f5 is the focal length of said subgroup G5p, dQ is the distance along the optical axis from said position Q to said aperture stop location, and NA is said numerical aperture, on the image-side, of the projection optical system.

An exposure apparatus that forms an image of a pattern of a mask onto a substrate over an exposure field, the exposure apparatus comprising:

• a) an illumination optical system that illuminates the mask;
• b) a dioptric projection optical system;
• c) said dioptric projection optical system comprising along an optical axis:
• i) a variable-size aperture stop disposed at a location along the optical axis, for determining an image-side numerical aperture NA;
• ii) a front lens group comprising a plurality of lens elements and positioned between the mask and said aperture stop;
• iii) a rear lens group comprising a plurality of lens elements and positioned between said aperture stop and the substrate;
• iv) wherein said system satisfies the condition:
• 0.005<dQ/{L×(1−NA)}<0.2
• v) L is the distance along the optical axis from the mask to the substrate, dQ is the distance along the optical axis from said aperture stop location to a position Q where a paraxial principal ray intersects the optical axis wherein said paraxial principal ray corresponds to ray from the substance side impinging upon said projection optical system parallel to the optical axis;
• and
• d) a stage system that positions the mask between said illumination optical system and said dioptric projection optical system and the substrate adjacent said projection optical system opposite the mask.

A device manufacturing method comprising the steps of:

• a) coating a photosensitive material onto a substrate;
• b) projecting onto said substrate an image of a pattern of a mask through a dioptric projection optical system, said dioptric projection optical system comprising along an optical axis:
• i) a variable-size aperture stop disposed at a location along the optical axis, for determining an image-guide numerical aperture NA;
• ii) a front lens group comprising a plurality of lens elements and positioned between said mask and said aperture stop;
• iii) a rear lens group comprising a plurality of lens elements and positioned between said aperture stop and said substrate;
• iv) wherein said system satisfies the condition:
• 0.005<dQ/{L×(1−NA)}<0.2
• wherein L is the distance along said optical axis from said mask to said image, dQ is the distance along said optical axis from said aperture stop location to a position Q where a paraxial principal ray intersects said optical axis, wherein said paraxial principal ray corresponds to a ray from said substrate side impinging upon said projection optical system parallel to the optical axis;
• and
• v) said aperture stop is variable in size;
• c) developing said photosensitive material on said substrate thereby forming a photoresist pattern;
• and
• d) forming a pattern in said substrate based on said photoresist pattern.

A method of manufacturing a dioptric projection optical system capable of forming an image of an object over an exposure field, the method comprising the steps of:

• a) providing an aperture stop at a location along an optical axis;
• b) arranging a plurality of lenses along said optical axis objectwise of said aperture stop;
• c) arranging a plurality of lenses along said optical axis imagewise of said aperture stop;
• and
• d) arranging said aperture stop location so as to satisfy the condition:
• 0.005<dQ/{L×(1−NA)}<0.2
• wherein L is the distance along the optical axis from the object to the image, dQ is the axial distance from said aperture stop location to a position Q where imagewise to objectwise traveling paraxial principal rays intersect the optical axis, and NA is the image-side numerical aperture.

A dioptric projection optical system for forming an image of a pattern of an object onto a workpiece over an exposure field, the system comprising:

• a first lens group, arranged in an optical path between the object and the image, having positive refractive power;
• a second lens group, arranged in an optical path between the first lens group and the image, having negative refractive power;
• a third lens group, arranged in an optical path between the second lens group and the image, having positive refractive power;
• a fourth lens group, arranged in an optical path between the third lens group and the image, having negative refractive power;
• a fifth lens group, arranged in an optical path between the fourth lens group and the image;
• and
• an aperture stop arranged in the fifth lens group,
• wherein at least two lenses of the fifth lens group are arranged in an optical path between the fourth lens group and the aperture stop,
• the fifth lens group has a lens, arranged adjacent to and imagewise of the aperture stop, with a concave surface facing objectwise, and
• said system has an imagewise maximum numerical aperture value including 0.65.