An optical reduction system for use in the photolithographic manufacture of semiconductor
devices having one or more quarter-wave plates operating near the long conjugate
end. A quarter-wave plate after the reticle provides linearly polarized light at
or near the beamsplitter. A quarter-wave plate before the reticle provides circularly
polarized or generally unpolarized light at or near the reticle. Additional quarter-wave
plates are used to further reduce transmission loss and asymmetries from feature
orientation. The optical reduction system provides a relatively high numerical
aperture of 0.7 capable of patterning features smaller than 0.25 microns over a
26 mm5 mm field. The optical reduction system is thereby well adapted to
a step and scan microlithographic exposure tool as used in semiconductor manufacturing.
Several other embodiments combine elements of different refracting power to widen
the spectral bandwidth which can be achieved.