Projection objective having a high aperture and a planar end surface

Projection objective for imaging a pattern provided in an object plane of the projection objective onto an image plane of the projection objective suitable for microlithography projection exposure machines comprising:

• a plurality of optical elements transparent for radiation at an operating wavelength of the projection objective;
• and
• a first high-index optical element and at least one second high-index optical element;
• wherein at least one optical element is a high-index optical element made from a high-index material with a refractive index n≧1.6 at the operating wavelength;
• and
• the first high-index optical element and the second high-index optical element are each made from a high-index material exhibiting birefringence defining an orientation of birefringence of each optical element, where the first and second high-index optical elements are installed differently with regard to the orientation of the birefringence such that effects of birefringence caused by the high-index optical elements are at least partly compensated.

Catadioptric projection objective for imaging a pattern provided in an object plane of the projection objective onto an image plane of the projection objective suitable for microlithography projection exposure machines comprising:

• a plurality of optical elements transparent for radiation at an operating wavelength of the projection obiective;
• and
• at least one concave mirror;
• wherein at least one optical element is a high-index optical element made from a high-index material with a refractive index n≧1.6 at the operating wavelength;
• and
• the projection objective has a last optical element closest to the image plane and wherein the last optical element is at least partly made of a high-index material with refractive index n>1.6.

Projection objective for imaging a pattern provided in an object plane of the projection objective onto an image plane of the projection objective suitable for microlithography projection exposure machines comprising:

• a plurality of optical elements transparent for radiation at an operating wavelength of the projection objective;
• wherein at least one optical element is a high-index optical element made from a high-index material with a refractive index n≧1.6 at the operating wavelength;
• and
• the projection objective is designed as an immersion objective adapted with reference to aberrations such that an image side working distance between a last optical element and the image plane is filled up with an immersion medium with a refractive index substantially greater than 1.

Catadioptric projection objective for imaging a pattern provided in an object plane of the projection objective onto an image plane of the projection objective suitable for microlithography projection exposure machines comprising:

• a plurality of optical elements transparent for radiation at an operating wavelength of the projection objective;
• and
• at least one concave mirror;
• wherein at least one optical element is a high-index optical element made from a high-index material with a refractive index n≧1.6 at the operating wavelength;
• and
• the projection objective is designed as a solid immersion objective having a finite image side working distance in the order of the operating wavelength or below such that evanescent fields exiting from an image side exit surface of the projection objective can be used for imaging.

Catadioptric projection objective for imaging a pattern provided in an object plane of the projection objective onto an image plane of the projection objective suitable for microlithography projection exposure machines comprising:

• a plurality of optical elements transparent for radiation at an operating wavelength of the projection objective;
• and
• at least one concave mirror;
• wherein at least one optical element is a high-index optical element made from a high-index material with a refractive index n≧1.6 at the operating wavelength;
• and
• an image side numerical aperture NA is greater than 1.3.

Projection objective for imaging a pattern provided in an object plane of the projection objective onto an image plane of the projection objective suitable for microlithography projection exposure machines comprising:

• a plurality of optical elements transparent for radiation at an operating wavelength of the projection objective;
• wherein at least one optical element is a high-index optical element made from a high-index material with a refractive index n≧1.6 at the operating wavelength;
• and
• the projection objective includes at least one aspheric lens group consisting of a number NASPL of at least two immediately consecutive aspheric lenses providing a number NASP of aspheric lens surfaces, where the condition AR>1 holds for an asphere ratio AR=NASP/NASPL.

Projection objective for imaging a pattern provided in an object plane of the projection objective onto an image plane of the projection objective suitable for microlithography projection exposure machines comprising:

• a plurality of optical elements transparent for radiation at an operating wavelength of the projection objective;
• a first, refractive objective part for imaging the pattern provided in the object plane into a first intermediate image;
• a second objective part including at least one concave mirror for imaging the first intermediate image into a second intermediate image;
• and
• a third objective part for imaging the second intermediate image onto the image plane;
• wherein at least one optical element is a high-index optical element made from a high-index material with a refractive index n≧1.6 at the operating wavelength.

Projection objective for imaging a pattern provided in an object plane of the projection objective onto an image plane of the projection objective suitable for microlithography projection exposure machines comprising:

• a plurality of optical elements transparent for radiation at an operating wavelength of the projection objective;
• wherein at least one optical element is a high-index optical element made from a high-index material with a refractive index n≧1.6 at the operating wavelength;
• an object-side numerical aperture NAObj is greater than 0.3;
• and
• a finite image-side working distance of the projection objective between an image-side exit surface of the projection objective and an image surface is substantially greater than the operating wavelength of the projection objective.

Projection objective for imaging a pattern provided in an object plane of the projection objective onto an image plane of the projection objective suitable for microlithography projection exposure machines comprising:

• a plurality of optical elements transparent for radiation at an operating wavelength of the projection objective;
• wherein at least one optical element is a high-index optical element made from a high-index material with a refractive index n≧1.6 at the operating wavelength;
• the projection objective has a last optical element closest to the image plane and wherein the last optical element is at least partly made of a high-index material with refractive index n>1.6;
• and
• a finite image-side working distance of the projection objective between an image-side exit surface of the projection objective and an image surface is substantially greater than the operating wavelength of the projection objective.

Projection objective for imaging a pattern provided in an object plane of the projection objective onto an image plane of the projection objective suitable for microlithography projection exposure machines comprising:

• a plurality of optical elements transparent for radiation at an operating wavelength of the projection objective;
• wherein at least one optical element is a high-index optical element made from a high-index material with a refractive index n≧1.6 at the operating wavelength;
• an image side numerical aperture NA is greater than 1.3;
• and
• a finite image-side working distance of the projection objective between an image-side exit surface of the projection objective and an image surface is substantially greater than the operating wavelength of the projection objective.