The AIMS-45, when used in scanner mode, can emulate image intensity as seen in resist on the wafer at scanner illumination conditions. We show that this feature makes AIMS-45 well-suited to inspect patterns treated with inverse lithography. We have used an inverse lithography technique by Mentor Graphics, to treat a random contact hole layout (drawn at minimal pitch 115nm) for imaging at NA 1.35. The combination of the dense 115nm pitch and available NA of 1.35 makes Quasar illumination necessary, and the inverse lithography treatment automatically generated optimal (model-based) Assist Features (AF) for all geometries in the design.

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