Optically stimulated electron emission contamination monitor and method
US6856403B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 11, 2003 |
| Grant date | Feb 15, 2005 |
| Priority date | — |
| Expiry date | Sep 11, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/33
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An apparatus and method for performing quality inspections on a test surface based on optically stimulated emission of electrons. In one embodiment, the apparatus comprises a device for producing optical radiation having a plurality of different spectrum lines, selecting at least one of the spectrum lines, and directing the selected spectrum line to the test surface, and circuitry for detecting a current of photoelectrons emitted from the test surface, generating a signal indicative of photoelectron current, and for indicating a condition of quality based on the generated signal indicative of the photoelectron current. In one embodiment, the method comprises producing optical radiation having a plurality of different spectrum lines, selecting at least one of the spectrum lines and directing the selected spectrum line to the test surface, detecting a current of photoelectrons emitted from the test surface and generating a signal indicative of photoelectron current, and indicating a condition of quality based on the generated signal indicative of the photoelectron current.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.