Aqueous anionic functional silica slurry and amine carboxylic acid compositions for selective nitride removal in polishing and methods of using them
US11186748B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 28, 2017 |
| Grant date | Nov 30, 2021 |
| Priority date | — |
| Expiry date | Oct 26, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/3212
- WIPO fieldBasic materials chemistry
- WIPO sectorChemistry
Abstract
The present invention provides aqueous chemical mechanical planarization polishing (CMP polishing) compositions comprising one or more dispersions of a plurality of elongated, bent or nodular anionic functional colloidal silica particles or their mixture with one or more dispersions of anionic functional spherical colloidal silica particles, one or more amine carboxylic acids having an isoelectric point (pI) below 5, preferably, an acidic amino acid or pyridine acid, and, preferably, one or more ethoxylated anionic surfactants having a C6 to C16 alkyl, aryl or alkylaryl hydrophobic group, wherein the compositions have a pH of from 3 to 5. The compositions enable good silicon nitride removal and selectivity of nitride to oxide removal in polishing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.