Automated method to check sidelobe overlap projected by adjacent apertures in attenuated phase-shift masks

A fast automated method to detect sidelobe overlap projected by adjacent apertures in attenuated phase-shift masks has been developed. This method approximates the sidelobe images by polygons, on which pattern operations are applied to quickly detect areas of overlap where unexpected images may occur. The feasibility of this method was demonstrated using hole patterns which contained 1.48 million pattern features. Calculation time was 4.3 hours, which was almost 3,500 times faster than aerial image simulation.