Method of determining a value of a parameter of interest, method of cleaning a signal containing information about a parameter of interest, device manufacturing method
US10795269B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 25, 2018 |
| Grant date | Oct 6, 2020 |
| Priority date | — |
| Expiry date | Nov 28, 2038 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70866
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The disclosure relates to methods of determining a value of a parameter of interest of a patterning process, and of cleaning a signal containing information about the parameter of interest. In one arrangement, first and second detected representations of radiation are obtained. The radiation is provided by redirection of polarized incident radiation by a structure. The first and second detected representations are derived respectively from first and second polarization components of the redirected radiation. An asymmetry in the first detected representation comprises a contribution from the parameter of interest and a contribution from one or more other sources of asymmetry. An asymmetry in the second detected representation comprises a larger contribution from said one or more other sources of asymmetry relative to a contribution from the parameter of interest. A combination of the first and second detected representations is used to determine a value of the parameter of interest.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.