Illumination system of a microlithographic projection exposure apparatus

摘要

An illumination system of a microlithographic projection exposure apparatus can include at least one transmission filter which has a different transmittance at least at two positions and which is arranged between a pupil plane and a field plane. The transmittance distribution can be determined such that it has field dependent correcting effects on the ellipticity. In some embodiments the telecentricity and/or the irradiance uniformity is not affected by this correction.

主权项

1. An apparatus having a plurality of pupil planes and a plurality of field planes, the apparatus comprising:
a first transmission filter having a first spatial transmittance distribution; and a second transmission filter having a second spatial transmittance distribution, wherein:
the first spatial transmittance distribution is identical to the second spatial transmittance distribution, or the first spatial transmittance distribution is a magnified image of the second spatial transmittance distribution, the first and second transmission filters are separated from each other by either: a) n pupil planes and n+1 or n−1 field planes; or b) m field planes and m+1 or m−1 pupil planes;
wherein n is an odd integer;m is an even integer distinct from zero;the field planes are conjugate to a mask plane;the pupil planes have a Fourier relation to the field planes; and the apparatus is a microlithographic projection exposure apparatus.