Control of surface potential of insulating specimens in surface analysis
US5990476A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 12, 1997 |
| Grant date | Nov 23, 1999 |
| Priority date | — |
| Expiry date | Nov 12, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N23/2273
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus effects a uniform surface potential on an insulating specimen in an x-ray photoelectron or a secondary ion emission instrument in which there is positive charging of an irradiation region. An area of the specimen including the irradiation region is flooded with a beam of low energy electrons to neutralize the positive charging, causing negative charging of the flooding area. Positive ions are directed onto the flooding area to neutralize the negative charging. The electron beam has an energy less than about 2 eV and an energy spread less than about 0.5 eV. The ratio of the beam distance to its diameter is less than about 10. The ions have an energy less than 10 eV.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.