Plasma ignition circuit
US11328900B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 17, 2020 |
| Grant date | May 10, 2022 |
| Priority date | — |
| Expiry date | Oct 23, 2040 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH05H1/36
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A plasma ignition circuit includes a transformer having a primary coil configured to couple an RF power supply. A first secondary coil is configured to couple a remote plasma source (RPS), and a second secondary coil. The plasma ignition circuit further includes a control switch having an input configured to couple the second secondary coil and an output configured to capacitively couple the RPS and a switch controller. The switch controller is configured to upon sensing a secondary RF voltage applied to the second secondary coil in response to an RF voltage applied by RF power supply to the primary coil, enable the control switch to capacitively apply the secondary RF voltage to the RPS to ignite a plasma within the RPS. Upon sensing a drop in plasma impedance when the plasma is ignited, disable the control switch to discontinue applying the secondary RF voltage to the RPS.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.