Patent ID: 8539393

Claim:
A method of shadowing effect modeling, comprising: by a computing device: receiving layout data for one or more layout designs; receiving information of a plurality of azimuthal angles of illumination; determining domain decomposition method (DDM) signals for an extreme ultraviolet (EUV) lithography mask to be made based on the one or more layout designs, the DDM signals being grouped into DDM signal sets, each of the DDM signal sets corresponding to a particular azimuthal angle of illumination in the plurality of azimuthal angles of illumination, wherein the determining DDM signals comprises: dividing the plurality of azimuthal angles of illumination into a first set of azimuthal angles of illumination and a second set of azimuthal angles of illumination; determining simulated DDM signals for the first set of azimuthal angles of illumination; and determining interpolated DDM signals for the second set of azimuthal angles of illumination based on the simulated DDM signals; processing the one or more layout designs based on the DDM signals; and storing results of the processing the one or more layout designs in a tangible non-transitory medium.