Method for copper CMP using polymeric complexing agents
US6821897B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 18, 2002 |
| Grant date | Nov 23, 2004 |
| Priority date | — |
| Expiry date | Jun 4, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/3212
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The invention provides a method of polishing a substrate comprising a metal layer comprising copper. The method comprises the steps of (i) providing a chemical-mechanical polishing system comprising a liquid carrier, a polishing pad, an abrasive, and a negatively-charged polymer or copolymer, (ii) contacting the substrate with the poloshing system, and (iii) abrading at least a portion of the substrate to polish the metal layer of the substrate. The negatively-charged polymer or copolymer comprises one or more monomers selected from sulfonic acids, sulfonates, sulfates, phosphonic acids, phosphonates, and phosphates, has a molecular weight of about 20,000 g/mol or more, and coats at least a portion of the abrasive such that the abrasive has a zeta potential value that is lowered upon interaction of the negatively-charged polymer or copolymer with the abrasive.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.