Abstract: A method is disclosed for repairing an opaque defect on a mask substrate. After examining one or more opaque patterns in a predetermined area of the mask substrate, at least one opaque defect in the opaque patterns is identified based on a difference between its light reflection rate and a reference reflection rate. A residue height of the opaque defect is further determined based on its light transmission rate, and a repair formula such as an etching dosage is devised based on the determined residue height.

Abstract: A method includes introducing an acid solution having ethanol and an acid to a substrate and cleaning the substrate using the acid solution; applying an ultrasonic wave to the acid solution substantially during the cleaning of the substrate; and performing a fine cleaning of the substrate after the cleaning of substrate with the acid solution.

Abstract: A reticle film stabilizing method which is suitable for stabilizing a reticle film on a reticle, is disclosed. The method includes subjecting the multilayer reticle film to VUV (vacuum ultraviolet) radiation prior to the megasonic cleaning process. The method increases the oxygen content of the reticle film, resulting in an oxygen-rich film surface which protects the reticle film from peeling during cleaning. Furthermore, the method enhances the surface wettability of the reticle film in a megasonic cleaning tank, thereby enhancing the cleaning efficacy.

Abstract: A method is disclosed for repairing an opaque defect on a mask substrate. After examining one or more opaque patterns in a predetermined area of the mask substrate, at least one opaque defect in the opaque patterns is identified based on a difference between its light reflection rate and a reference reflection rate. A residue height of the opaque defect is further determined based on its light transmission rate, and a repair formula such as an etching dosage is devised based on the determined residue height.