A method for optically transferring a lithographic pattern corresponding to an
integrated circuit utilizing a high transmission attenuated phase-shift mask onto
a semiconductor substrate by use of an optical exposure tool. The method comprising
the steps of generating a diffraction pattern corresponding to the lithographic
pattern, where the diffraction pattern indicates a plurality of spatial frequency
components corresponding to the lithographic pattern; determining which of the
spatial frequency components need to be captured by a lens in the optical exposure
tool in order to accurately reproduce the lithographic pattern; determining a set
of illumination conditions required for the optical exposure tool to capture the
spatial frequency components necessary for accurately reproducing the lithographic
pattern; and illuminating the high transmission attenuated phase-shift mask with
this set of illumination conditions.