Joint electron-optical columns for flood-charging and image-forming in voltage contrast wafer inspections
US12165838B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 27, 2019 |
| Grant date | Dec 10, 2024 |
| Priority date | — |
| Expiry date | Sep 2, 2040 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/2817
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A scanning electron microscopy system may include an electron-optical sub-system and a controller. The electron-optical sub-system may include an electron source and an electron-optical column configured to direct an electron beam to a sample. The electron-optical column may include a double-lens assembly, a beam limiting aperture disposed between a first and second lens of the double-lens assembly, and a detector assembly configured to detect electrons scattered from the sample. In embodiments, the controller of the scanning electron microscopy system may be configured to: cause the electron-optical sub-system to form a flooding electron beam and perform flooding scans of the sample with the flooding electron beam; cause the electron-optical sub-system to form an imaging electron beam and perform imaging scans of the sample with the imaging electron beam; receive images acquired by the detector assembly during the imaging scans; and determine characteristics of the sample based on the images.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.