Using a crystallographic etched silicon sample to measure and control the electron beam width of a SEM
US6396059B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 10, 2000 |
| Grant date | May 28, 2002 |
| Priority date | — |
| Expiry date | Jul 10, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J37/263
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A system and method is provided for measuring and determining the resolution of a SEM imaging system employing a crystallographic etched sample with a re-entrant cross-sectional profile. A re-entrant or negative profile is employed because the top-down view seen by the SEM is very sharp due to the fact the edge of the profile has zero width. Therefore, any apparent width seen in the signal is a function of the electron beam width alone. Scanning the beam across the profile provides a signal that moves from a first state to a second state. The time period or sloping portion of the signal from the first state to the second state provides a direct correlation to the electron beam width. Thus, scanning across the sample allows for a calculation of the electron beam width. By scanning across features of different orientations, the shape of the electron beam can be determined. Alternatively, by rotating the electron beam and scanning across the same feature, the shape of the electron beam can be determined. A system can utilize this information to adjust the resolution of the SEM or a display displaying the image.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.