Method and an apparatus for offsetting plasma bias voltage in bi-polar electro-static chucks
US5933314A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 27, 1997 |
| Grant date | Aug 3, 1999 |
| Priority date | — |
| Expiry date | Jun 27, 2017 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T279/23
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A control circuit configured to control a reference voltage of a reference node of an electrostatic chuck power supply is disclosed. The electrostatic chuck power supply is configured to clamp a substrate to a bipolar electrostatic chuck. The electrostatic chuck has a first buried conductor and a second buried conductor. The electrostatic chuck power supply has a first output configured for being coupled with the first buried plate. The first output has a first output voltage referenced to the reference voltage of the reference node. The electrostatic chuck power supply also has a second output configured for being coupled with the second buried plate. The first output has a first output voltage referenced to the reference voltage of the reference node. The control circuit includes: a first resistor coupled in series with the first output; a first amplifier coupled to the first resistor for sensing a voltage drop across the first resistor; a second resistor in series with said second output; and a second amplifier coupled to the second resistor for sensing a voltage drop across the second resistor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.