Device-like overlay metrology targets displaying Moiré effects
US11355375B2 · kind B2 · utility
2Cited by
11References
21Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 16, 2020 |
| Grant date | Jun 7, 2022 |
| Priority date | — |
| Expiry date | Jul 19, 2040 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70633
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A metrology system and metrology methods are disclosed. The metrology system comprises a set of device features on a first layer of a sample, a first set of target features on a second layer of the sample and overlapping the set of device features, and a second set of target features on the second layer of the sample and overlapping the set of device features. Relative positions of a first set of Moiré fringes and a second set of Moiré fringes indicate overlay error between the first layer of the sample and the second layer of the sample.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.