Carrier having pistons for distributing a pressing force on the back surface of a workpiece
US6336853B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 31, 2000 |
| Grant date | Jan 8, 2002 |
| Priority date | — |
| Expiry date | Mar 31, 2020 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB24B37/30
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
An apparatus and method are disclosed for a carrier that is able to create independently controllable pressure zones on the back surface of a wafer while the front surface of the wafer is being planarizing against an abrasive surface. The carrier has a central disk shaped recess surrounded by a plurality of concentric ring shaped recesses. The recesses are covered by a diaphragm thereby creating a central disk shaped plenum and a plurality of surrounding ring shaped plenums. A central disk shaped piston and a plurality of surrounding ring shaped pistons are suspended on the diaphragm so that a portion of each piston may move in and out of their corresponding plenum in the carrier. An independently controllable fluid communication path is placed in fluid communication with each plenum thereby allowing the pressure exerted on each piston to be independently controllable.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.