MOFIFICATION OF A PROJECTION IMAGING SYSTEM WITH A NON-CIRCULAR APERTURE AND A METHOD THEREOF

摘要

An imaging tool (10) for use with a mask (16) with features oriented along at least an x-axis or a y-axis where the x-axis extends in directions substantially perpendicular to the directions of the y-axis. The tool has a condenser lens (20) and an objective lens (18). The condenser lens has a condenser aperture (30) with four-sides and four corners that are located in a condenser lens pupil plane. The sides of the condenser aperture are oriented in substantially the same direction as either the x-axis or the y-axis. The condenser lens is positioned to place at least a portion or any illumination on the mask and then into an objective lens. At least one of the corners of the condenser aperture in the condenser plate may have a substantially rounded shape. Additionally, the mask may have at least one artifact added to at least one corner of the features for optical proximity correction.