Compressible non-reticulated polyurea polishing pad
US11548114B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 11, 2021 |
| Grant date | Jan 10, 2023 |
| Priority date | — |
| Expiry date | Sep 11, 2041 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/31053
- WIPO fieldMacromolecular chemistry, polymers
- WIPO sectorChemistry
Abstract
The invention provides a polishing pad suitable for polishing at least one of semiconductor, optical, magnetic or electromechanical substrates. It includes a polyurea polishing layer and a polyurea matrix. The polyurea has a soft segment being a copolymer of aliphatic fluorine-free polymer groups and a fluorocarbon having a length of a least six carbons. The polyurea matrix being cured with a curative agent and including gas or liquid-filled polymeric microelements. The polyurea matrix has a bulk region and a transition region adjacent the bulk region that extends to the polishing layer. The polymeric microelements in the transition region decrease in thickness as they approach the polishing layer with thickness of the compressed microelements adjacent the polishing layer being less than fifty percent of a diameter of the polymeric microelements in the bulk region. The polishing layer remains hydrophilic during polishing in shear conditions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.