| 摘要 |
PROBLEM TO BE SOLVED: To provide a catadioptric projection objective system suitable for use in a vacuum ultraviolet range, which has potential for a very high image-side numerical aperture that may reach values that enable immersion lithography at numerical apertures NA>1.SOLUTION: A catadioptric projection objective lens, for imaging a pattern provided in an object plane of a projection objective lens onto an image plane of a projection objective system, includes: a first refractive objective lens part for imaging the pattern provided in the object plane into a first intermediate image; a second objective lens part having at least one concave mirror for imaging the first intermediate image into a second intermediate image; and a third refractive objective lens part for imaging the second intermediate imaging onto the image plane. The projection objective lens has a maximum lens diameter D, a maximum image field height Y', and an image-side numerical aperture NA, and satisfies a condition COMP1<10, where COMP1 is equal to D/(Y'×NA).SELECTED DRAWING: Figure 1 |
