Dechucking method and apparatus for workpieces in vacuum processors
US6790375B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 30, 1998 |
| Grant date | Sep 14, 2004 |
| Priority date | — |
| Expiry date | Sep 30, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02N13/00
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A glass workpiece being processed in a vacuum plasma processing chamber is dechucked from a monopolar electrostatic chuck by gradually reducing the chucking voltage during processing while maintaining the voltage high enough to clamp the workpiece. A reverse polarity voltage applied to the chuck at the end of processing assists in dechucking. The workpiece temperature is maintained at a high value at the end of processing to assisting in dechucking. Peak current flowing through the chuck during lifting of the workpiece from the chuck controls the amplitude and/or duration of the reverse polarity voltage during the next dechucking operation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.