Differential numerical aperture methods and device
US6750968B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 2, 2001 |
| Grant date | Jun 15, 2004 |
| Priority date | — |
| Expiry date | Mar 20, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2021/214
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Devices and methods for differential numerical aperture analysis of samples, utilizing angle-of-incidence measurements resulting from variable illumination or observation numerical apertures, or both. Metrology applications are provided, and more particularly including scatterometer, ellipsometer and similar analysis methods, including bi-directional reflectance or transmission distribution function measurement. The provided devices and methods enable analysis of critical dimensions of samples utilizing a minimum of moving parts, with the range of striking or scattering angles varied by a variable numerical aperture or apertures.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.