Method and apparatus for automated beam optimization in a scanning electron microscope
US7358493B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 8, 2005 |
| Grant date | Apr 15, 2008 |
| Priority date | — |
| Expiry date | May 24, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01J2237/2817
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method and apparatus according to the present invention define optimal conditions for a scanning electron microscope (SEM), preferably a critical dimension scanning electron microscope (CDSEM). The present invention provides an image quality monitor that utilizes image processing and optimization to maintain image quality at a desired level. Images from a stage sample are automatically collected, while microscope operational parameters are determined based on image processing to enable continuous monitoring of microscope operation. The technique may be performed manually or automatically and generates set points for beam conditioning elements to produce or maintain ideal beam conditions to enhance image quality. The present invention generates data indicating optimized values for each beam alignment parameter. The optimized values are applied to the internal microscope values to optimize the beam. The results may be provided to the technician, a data storage system or directly to the microscope control mechanisms.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.