Controlled-viscosity CMP casting method
US9452507B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Dec 19, 2014 |
| Grant date | Sep 27, 2016 |
| Priority date | — |
| Expiry date | Dec 19, 2034 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC08J2375/04
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The invention provides a method of manufacturing a polishing pad suitable for planarizing at least one of semiconductor, optical and magnetic substrates. The method obtains a liquid polyurethane material formed from an isocyanate-terminated molecule and a curative agent. The liquid polyurethane material contains 4.2 to 7.5 weight percent fluid-filled polymeric microspheres in the isocyanate-terminated molecule. The fluid-filled polymeric microspheres are a blend of preexpanded and unexpanded fluid-filled polymeric microspheres. The liquid polyurethane material contains a blend of preexpanded and unexpanded fluid-filled polymeric microspheres having a relative viscosityof 1.1 to 7. Then the liquid polyurethane material solidifies into a polyurethane matrix that contains preexpanded and expanded fluid-filled polymeric microsphere for forming the polishing pad.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.