Cerium oxide powder for abrasive and CMP slurry comprising the same
US8333815B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 30, 2008 |
| Grant date | Dec 18, 2012 |
| Priority date | — |
| Expiry date | Apr 14, 2029 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC01P2004/20
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
Disclosed are cerium oxide powder for an abrasive; CMP slurry including the same; and a shallow trench isolation (STI) process using the CMP slurry. At least two kinds of cerium oxides prepared by using cerium carbonates having different crystal structures are mixed in an appropriate ratio and used as an abrasive for CMP slurry, thereby adjusting required polishing properties of the CMP slurry. Also, in a disclosed method of preparing a cerium carbonate, the crystal structure of the cerium carbonate can be easily controlled. Based on the finding that in a cerium oxide for an abrasive, the kind of improved polishing property depends on the crystal structure of a cerium carbonate, at least one from among polishing properties, such as the polishing rate of a silicon oxide layer, the polishing rate of a silicon nitride layer, the polishing selectivity between the silicon oxide layer and the silicon nitride layer, and WIWNU, can be adjusted by using at least two kinds of cerium oxides selected from the group including (i) a cerium oxide prepared by using a lanthanite-(Ce) crystal structured cerium carbonate, (ii) a cerium oxide prepared by using an orthorhombic crystal structured cerium…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.