Endpoint detection in chemical-mechanical polishing of cloisonne structures
US6291351A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 2000 |
| Grant date | Sep 18, 2001 |
| Priority date | — |
| Expiry date | Jun 28, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/3163
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A method is described for fabricating a cloisonne structure, in which a top surface of a metal oxide layer is made coplanar with a top surface of a metallic structure formed on a substrate. A nitride layer is deposited on at least the top surface of the metallic structure, and the metal oxide layer is deposited over the metallic structure and the nitride layer. The metal oxide layer is then polished by a chemical-mechanical polishing (CMP) process using a slurry, to expose the nitride layer on the top surface of the metallic structure. Polishing of the nitride layer causes ammonia to be generated in the slurry. The ammonia is extracted as a gas from the slurry, and a signal is generated in accordance with the ammonia concentration. The CMP process is terminated in accordance with a change in the signal. In a preferred embodiment, the metal oxide is aluminum oxide, the nitride is aluminum nitride, and the nitride layer is deposited as a conformal layer on the substrate and the metallic structure.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.