LITHOGRAPHIC SYSTEMS AND METHODS WITH EXTENDED DEPTH OF FOCUS

摘要

Apparatus for increasing the depth of focus in a lithographic system, comprising: optics for imaging a reticle or photomask onto a lithographic recording medium having a threshold of exposure; a pupil plane function that alters the aerial image of the lithographic imaging system such that part of the aerial image is above a recording threshold of the lithographic recording medium over the extended depth of focus, the pupil plane function altering a system response function and the aerial image by affecting phase of a wavefront imaged by the optics.