Patent ID: 7615318

Claim:
A method for printing design features within a photosensitive material using alternating Phase Shift Mask technology based on a double mask exposure strategy, comprising the steps of: determining at least first, second and third design features adjacent one to the other, of which said first design feature has critical dimensions whereas said second and third design features do not have critical dimensions; defining a phase shift mask and an associated binary trim mask, such that opposite edges of said first design feature are to be defined by the phase shift mask, that a first edge of said second design feature is to be defined by the phase shift mask while a second opposite edge thereof is to be defined by the binary trim mask, and that all edges of said third design feature are to be defined by the binary trim mask; determining that said second design feature cannot be subject to an upsizing effect due to its proximity with said third design feature; and, as a result, modifying the phase shift mask definition and the associated binary trim mask definition, so that said phase shift mask becomes suitable for defining said opposite edges of said first design feature along with said first and second opposite edges of said second design feature, and for defining one edge of said third design feature, whereas said binary trim mask becomes suitable for defining another opposite edge of said third design feature with upsizing thereof; and fabricating the phase shift mask and the binary trim mask over a resist layer, in accordance with their respective definition thus modified, and lighting the resist layer through the phase shift mask and then through the binary trim mask.