Metrology method, target and substrate
US11428521B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 5, 2021 |
| Grant date | Aug 30, 2022 |
| Priority date | — |
| Expiry date | Nov 5, 2041 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70683
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A diffraction measurement target that has at least a first sub-target and at least a second sub-target, and wherein (1) the first and second sub-targets each include a pair of periodic structures and the first sub-target has a different design than the second sub-target, the different design including the first sub-target periodic structures having a different pitch, feature width, space width, and/or segmentation than the second sub-target periodic structure or (2) the first and second sub-targets respectively include a first and second periodic structure in a first layer, and a third periodic structure is located at least partly underneath the first periodic structure in a second layer under the first layer and there being no periodic structure underneath the second periodic structure in the second layer, and a fourth periodic structure is located at least partly underneath the second periodic structure in a third layer under the second layer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.