LARGE AREA DEFECT MONITOR TOOL FOR MANUFACTURE OF CLEAN SURFACES

摘要

A method and resulting system (602) for directing generally collimated illumination from a source (623) at an oblique angle to a surface under inspection (SUS) (611) to produce a scattered nonspecular energy substantially normal to the SUS and for observing the scattered nonspecular energy in one of a plurality of fractional windows of a viewed image of the SUS via a plurality of focussing elements (622). Such arrangement results in simultaneous and significant throughput and sensitivity enhancement over existing art. The method can be enhanced further wherein the observing step is performed through suitable relative motion of the scattering image over the imaging plane to permit over-sampling. Imaging sensors (621) with an aggregate 2000 x 2000 pixel resolution could image a 200 mm wafer (611) to 100 microns pitch.