Cross hatched metrology marks and associated method of use
US7671990B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 6, 2007 |
| Grant date | Mar 2, 2010 |
| Priority date | — |
| Expiry date | Nov 30, 2027 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03F7/70683
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
The present invention is directed to novel metrology marks and methods for their use. The marks comprise cross hashed overlay metrology marks formed on a substrate including a plurality of target regions. The mark including a first grating structure formed in one layer of a target region and including a second grating structure formed in another layer of the target region. The periodic features of the first and second grating structures are oriented substantially orthogonal one another to form a cross-hatched metrology target in the target region. Additionally, the patent discloses methods of employing the metrology marks to obtain overlay metrology measurements.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.