Swinging objective retarding immersion lens electron optics focusing, deflection and signal collection system and method
US6605805B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Mar 28, 2002 |
| Grant date | Aug 12, 2003 |
| Priority date | — |
| Expiry date | Mar 28, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/1035
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A swinging objective retarding immersion lens system and method therefore which provide a low voltage electron beam with high beam current, relatively high spatial resolution, a relative large scan field, and high signal collection efficiency. The objective lens includes a magnetic lens for generating a magnetic field in the vicinity of the specimen to focus the particles of the particle beam on the specimen, an electrode having a potential for providing a retarding field to the particle beam near the specimen to reduce the energy of the particle beam when the beam collides with the specimen; a deflection system including a plurality of deflection units situated along the beam axis for deflecting the particle beam to allow scanning on the specimen with large area, at least one of the deflection units located in the retarding field of the beam, the remainder of the deflection units located within the central bore of the magnetic lens; and a annular detection unit with a relatively small aperture, located underneath the primary beam define aperture, to capture secondary electron (SE) and backscattered electrons (BSE).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.