Projection illumination arrangement for Large Scale Integrated Circuit manufacture

摘要

the arrangement has a light source (11) with which a photo mask (20) is illuminated. A diffracted light beam from the photo mask is focussed onto a free-lying substrate (21) via an optical projection system (6) so that a circuit pattern is projected. An optical projection system has a first semi-transparent mirror (1), a first concave mirror (2) for reflecting a light beam reflected or transmitted by the first semi-transparent mirror, a second semi-transparent mirror (3) separate from the first and a second concave mirror (4) for reflecting a light beam reflected or transmitted by the second semi-transparent mirror.