Method and device for focusing in an inspection system
US10107761B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Dec 21, 2016 |
| Grant date | Oct 23, 2018 |
| Priority date | — |
| Expiry date | Dec 21, 2036 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N2201/0638
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An inspection apparatus including: a substrate holder configured to hold a substrate; an aperture device; and an optical system configured to direct a first measurement beam of radiation onto the substrate, the first measurement beam having a first intensity distribution, and configured to direct a second focusing beam of radiation onto the substrate at a same time as the first measurement beam is directed on the substrate, the second focusing beam having a second intensity distribution, wherein at least part of the second intensity distribution is spatially separated from the first intensity distribution at least at the substrate and/or the aperture device.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.