Ion source with biased extraction plate
US10923306B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 13, 2019 |
| Grant date | Feb 16, 2021 |
| Priority date | — |
| Expiry date | Mar 13, 2039 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/31701
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An indirectly heated cathode ion source having an electrically isolated extraction plate is disclosed. By isolating the extraction plate, a different voltage can be applied to the extraction plate than to the body of the arc chamber. By applying a more positive voltage to the extraction plate, more efficient ion source operation with higher plasma density can be achieved. In this mode the plasma potential is increased, and the electrostatic sheath reduces losses of electrons to the chamber walls. By applying a more negative voltage, an ion rich sheath adjacent to the extraction aperture can be created. In this mode, conditioning and cleaning of the extraction plate is achieved via ion bombardment. Further, in certain embodiments, the voltage applied to the extraction plate can be pulsed to allow ion extraction and cleaning to occur simultaneously.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.