METHOD AND APPARATUS FOR REMOVING CONTAMINANTS OFF A RETICLE

摘要

A method for removing a soft defect from a reticle, the reticle comprising a substrate made from material transparent to UV irradiation and having a front surface and a back opposite surface, the front surface provided with a pattern on an absorber coating layer, the soft defect being located on the coating layer, on a space of the pattern or at another location within a volume enclosed between a pellicle substantially covering the front surface and the front surface of the reticle. The method comprises receiving information on the location of the soft defect; generating a pulsed laser beam using the pulsed laser source; and based on the information directing the pulsed laser beam through the back surface of the reticle and into the substrate and focusing the beam on the target location within the substrate adjacent the location of the soft defect or directly on the location of the soft defect.