Particle detectors
US6888140B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | May 30, 2003 |
| Grant date | May 3, 2005 |
| Priority date | — |
| Expiry date | Aug 21, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/2608
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A signal detector for detecting electrically charged particles in a gaseous medium has an electrode having a tip region for gathering charged particles. The electrode is connected to a voltage source for applying a voltage that generates electro-static field for attracting the particles to the electrode, and at least part of the tip region has a radius of curvature which is sufficiently small or (in the case of a point tip or sharp edge) infinitesimally small so as to create a localised high intensity electro-static field which defines a detection zone in which, in use, charge particles are accelerated by the electric field so as to ionise gas molecules in the zone and thus amplify the signal to be received by the detector. The received signal is supplied through an output of the detector. The detector may be provided in a sample chamber of a scanning electron microscope.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.