Dual-spot phase-sensitive detection
US7002695B2 · kind B2 · utility
7Cited by
2References
24Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | May 7, 2002 |
| Grant date | Feb 21, 2006 |
| Priority date | — |
| Expiry date | May 7, 2022 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L22/00
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Apparatus for optical assessment of a sample includes a radiation source, adapted to generate a beam of coherent radiation, and traveling lens optics, adapted to focus the beam so as to generate first and second spots on a surface of the sample and to scan the spots together over the surface. Collection optics are positioned to collect the radiation scattered from the first and second spots and to focus the collected radiation so as to generate a pattern of interference fringes. A detector detects a change in the pattern of the interference fringes as the spots are scanned over the surface.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.