Optimized trench/via profile for damascene processing

摘要

The reliability of in-laid metallization patterns, e.g., of copper or copper alloy, is significantly enhanced by voidlessly filling recesses in a substrate by an electroplating process, wherein "pinching-off" of the recess opening due to earlier formation of overhanging nucleation/seed layer deposits at the corners of the opening as a result of increased rates of deposition thereat is prevented. Embodiments include selectively tapering the width of the recess mouth opening to provide a wider opening at the substrate surface by means of a directed beam etching or ablation process while rotating the substrate, which tapered width profile effectively prevents formation of overhanging deposits thereat which can result in occlusion and void formation during filling of the recesses by electroplating.