Collection of secondary electrons through the objective lens of a scanning electron microscope
US6946654B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 23, 2001 |
| Grant date | Sep 20, 2005 |
| Priority date | — |
| Expiry date | Aug 15, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/24485
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A high resolution scanning electron microscope collects secondary Auger electrons through its objective lens to sensitively determine the chemical make-up with extremely fine positional resolution. The system uses a magnetic high resolution objective lens, such as a snorkel lens or a dual pole magnetic lens which provides an outstanding primary electron beam performance. The Auger electrons are deflected from the path of the primary beam by a transfer spherical capacitor. The primary beam is shielded, by a tube or plates, as it traverses the spherical capacitor to prevent aberration of the primary beam and the external wall of the shield maintains a potential gradient related to that of the spherical capacitor to reduce aberration of the primary electron beam. The coaxial configuration of the primary electron beam and the collected secondary electron beam allows the Auger image to coincide with the SEM view.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.