A method of rapidly estimating binding lithography structures in an integrated circuit layout

摘要

The present invention provides a lithography difficulty measure which is a function of the energy ratio factor, which has a ratio of "difficult to print" energy to "easy to print" energy of the diffraction orders along an angular coordinate i {of Spatial frequency space, an energy entropy factor having the energy entropy of the diffraction orders along the angular coordinate ft, a phase entropy factor having the phase entropy of the diffraction orders along the angular coordinate 6 ", and a total energy entropy factor having the total energy entropy of the diffraction orders (430, 440). The "difficult to print" energy has energy of the diffraction orders at values of the normalized radial coordinates r of the spatial frequency space in an environment of r = 0 and in an environment of r = 1, and the "easy to print" energy has energy of Diffraction orders lying at intermediate values of the normalized radial coordinates r between the neighborhood of r = 0 and the neighborhood of r = 1. The value of lithographic difficulty metric may be used to determine structures in a design layout that are binding structures in an optimization calculation. The lithographic difficulty measure can be used to design integrated circuits having good, relatively easy-to-print properties.