Method and apparatus for sensing a wafer in a carrier
US6568991B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 28, 2001 |
| Grant date | May 27, 2003 |
| Priority date | — |
| Expiry date | Aug 28, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/6838
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
The invention is a carrier that determines if a wafer has been properly loaded. The carrier includes a body having a cavity covered by a membrane, thereby forming an initial plenum. One or more annular ribs may extend from the body to the membrane to divide the initial plenum into a plurality of plenums. A sensor is positioned within one of the plenums to detect the presence of the wafer. Pump(s) with pressure regulators may be used to pressurize the plenum(s). A first plenum may be pressurized sufficient to hold the wafer to the membrane by creating a partial vacuum between the membrane and the wafer. A second plenum may be pressurized sufficient to urge the membrane away from the sensor if the wafer is not properly loaded in the carrier. If the membrane is near the sensor, the wafer has been properly loaded into the carrier.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.