摘要 |
<p>The present invention provides a chemical-mechanical polishing slurry for use in removing copper overlaying a tantalum-based barrier layer during the fabrication of a copper damascene structure, and a method of retarding the corrosion of copper lines during the chemical-mechanical polishing of a copper damascene structure using the slurry. The slurry according to the invention includes an oxidizing agent that releases free radicals and a non-chelating free radical quencher that is effective to retard the corrosion of the copper lines during chemical-mechanical polishing. Preferred oxidizing agents that release free radical used in the slurry according to the invention include peroxides, peroxydiphosphates, and persulfates. Preferred non-chelating free radical quenchers used in the slurry according to the invention include ascorbic acid, thiamine, 2-propanol, and alkyl glycols, with ascorbic acid being most preferred.</p> |