Resonator method and system for distinguishing characteristics of surface features or contaminants
US7214932B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 27, 2005 |
| Grant date | May 8, 2007 |
| Priority date | — |
| Expiry date | Jul 26, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N21/21
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A resonator method and system for distinguishing characteristics of surface features or contaminants provides improved inspection or surface feature detection capability in scanning optical systems. A resonator including a surface of interest in the resonant path is coupled to a detector that detects light leaving the resonator. Changes in the resonance peak positions and peak intensities are evaluated against known changes for standard scatters in order to determine the material characteristics of an artifact at the surface of interest that causes a resonance change. The lateral size of the artifact is determined by de-convolving a known illumination spot size with the changing resonance characteristics, and the standard scatterer data is selected in conformity with the determined artifact size. The differential analysis using resonance peak shifts corresponding to phase and amplitude information provides an identification algorithm that identifies at least one artifact/material type is identified from matching known behaviors of artifacts/materials.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.