Overlay marks, methods of overlay mark design and methods of overlay measurements
US8330281B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 30, 2007 |
| Grant date | Dec 11, 2012 |
| Priority date | — |
| Expiry date | Nov 2, 2027 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S438/975
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
An overlay mark for determining the relative shift between two or more successive layers of a substrate is disclosed. The overlay mark includes at least one test pattern for determining the relative shift between a first and a second layer of the substrate in a first direction. The test pattern includes a first set of working zones and a second set of working zones. The first set of working zones are disposed on a first layer of the substrate and have at least two working zones diagonally opposed and spatially offset relative to one another. The second set of working zones are disposed on a second layer of the substrate and have at least two working zones diagonally opposed and spatially offset relative to one another. The first set of working zones are generally angled relative to the second set of working zones thus forming an “X” shaped test pattern.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.