Projection objective for microlithography

摘要

A projection objective for imaging a pattern arranged in an object surface of the projection objective into an image surface of the projection objective with a demagnified imaging scale has a plurality of optical elements which are arranged along an optical axis of the projection objective and are configured in such a way that a defined image field curvature of the projection objective is set in such a way that an object surface that is curved convexly with respect to the projection objective can be imaged into a planar image surface. What can be achieved given a suitable setting of the object surface curvature is that a gravitation-dictated bending of a mask does not have a disturbing effect on the imaging quality.

主权项

1. A projection objective configured to image a pattern of a reticle arranged in an object surface of the projection objective into an image surface of the projection objective with a demagnified imaging scale, comprising:
a plurality of optical elements configured to image the object surface into the image surface, and a system configured to dynamically adapt the projection objective upon transition to an other type of reticle, wherein the system comprises at least one manipulator configured to alter an optical surface of an active mirror, to thereby adapt the projection objective to the other type of reticle without reconstructing the projection objective.