Metrology of multi-layer stacks
US10591284B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 27, 2019 |
| Grant date | Mar 17, 2020 |
| Priority date | — |
| Expiry date | Feb 27, 2039 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01B11/14
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Techniques for removing interferometry signal phase variations caused by distortion and other effects in a multi-layer stack include: providing an electronic processor sample interferometry data acquired for the stack using a low coherence imaging interferometry system; transforming, by the electronic processor, the sample interferometry data to a frequency domain; identifying a non-linear phase variation from the sample interferometry data in the frequency domain, in which the non-linear phase variation is a result of dispersion introduced into a measurement beam by the test sample; and removing the non-linear phase variation from the sample interferometry data thereby producing compensated interferometry data.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.