Cold cathode ion gauge
US7098667B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Nov 23, 2004 |
| Grant date | Aug 29, 2006 |
| Priority date | — |
| Expiry date | Nov 23, 2024 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J41/06
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A cold cathode ion gauge is provided that is suitable for use in a high vacuum and in the presence of contaminating gases. By decreasing the discharge current and, more precisely, decreasing the charge current density received by the gauge electrodes, and using certain type of materials for the gauge electrodes, the mechanism by which insulating films are deposited on surface of the electrodes is attenuated and the life of the gauge is significantly prolonged. The gauge discharge current can be decreased by providing a large resistor in series with the anode, while the charge current density can be decreased by using an electrode with larger surface area, which can be achieved by fabricating grooves or fans on electrodes and by using low electron backscattering and low secondary emission materials, like carbon.Another concept of constant current mode is also proposed in this invention for extending the lifetime of CCIGs that are used for vacuum containing unfriendly gases.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.