Abstract: A method for repairing defects in a photolithographic mask for use in patterning semiconductor wafers introduces a pre-selected phase error selected to sum with a phase error of a defect repair material, yielding a desired composite phase error relative to light passing through the substrate alone, e.g., 180°. Substrate phase error may be introduced by modifying its thickness. For example, after any opaque layer material within a repair zone surrounding the defect is removed, the substrate, too, is removed within the repair zone to a pre-selected depth, forming a lacuna. Repair material is then deposited in the lacuna and in the remainder of the repair zone to a level substantially equal to the top surface of the opaque layer, yielding a desired, combined phase error and attenuation matching those of defect free regions of the mask where the opaque layer has not been removed.

Abstract: An alignment or overlay mark with improved signal to noise ratio is disclosed. Improved signal-to-noise ratio results in greater depth of focus, thus improving the performance of the alignment mark. The alignment mark comprises a zone plate having n concentric alternating opaque and non-opaque rings. Light diffracted by either the odd or even rings are cancelled while light diffracted by the other of the odd or even rings are added.

Abstract: An alignment or overlay mark with improved signal to noise ratio is disclosed. Improved signal-to-noise ratio results in greater depth of focus, thus improving the performance of the alignment mark. The alignment mark comprises a zone plate having n concentric alternating opaque and non-opaque rings. Light diffracted by either the odd or even rings are cancelled while light diffracted by the other of the odd or even rings are added.

Abstract: A method of transferring a pattern onto a substrate during IC fabrication is disclosed. The substrate is coated with a photosensitive layer having compounds dissolved in a solvent. Roughness on the sidewalls of the photosensitive layer is eliminated or reduced by evaporating the solvent without using elevated temperatures.