Slurry for chemical-mechanical polishing copper damascene structures
US6508953B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 19, 2000 |
| Grant date | Jan 21, 2003 |
| Priority date | — |
| Expiry date | Oct 19, 2020 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC23F3/00
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
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 radicals 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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.