摘要 |
<P>PROBLEM TO BE SOLVED: To provide a catadioptric projection objective suitable for use in a vacuum ultraviolet range, which has potential for very high image side numerical aperture which may be extended to values allowing immersion lithography at numerical apertures NA>1. <P>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 has: 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 including at least one concave mirror for imaging the first intermediate imaging 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<SB POS="POST">max</SB>, a maximum image field height Y', and an image side numerical aperture NA. COMP1 is equal to D<SB POS="POST">max</SB>/(Y'*NA<SP POS="POST">2</SP>) and a condition COMP1<10 is true. <P>COPYRIGHT: (C)2012,JPO&INPIT |