Time-based wafer de-chucking from an electrostatic chuck having separate RF BIAS and DC chucking electrodes
US7813103B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 11, 2007 |
| Grant date | Oct 12, 2010 |
| Priority date | — |
| Expiry date | Jan 1, 2029 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/68742
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An electrostatic chuck in a reactor chamber has a cathode electrode insulated from ground, a chucking electrode insulated from the cathode electrode and a dielectric layer overlying the chucking electrode that provides a workpiece support surface. A D.C. chucking voltage supply is coupled to the chucking electrode. An RF power generator is coupled to the cathode electrode. A voltage sensing apparatus is coupled to the chucking electrode and to the cathode electrode to monitor the voltage difference between them during discharge after removal of RF and DC power at the conclusion of processing. The reactor includes a controller programmed to raise the lift pins during electrode discharge as soon as the voltage sensing apparatus detects equal voltages simultaneously on the chucking and cathode electrodes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.