Wafer alignment mark scheme
US9640487B2 · kind B2 · utility
0Cited by
2References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 16, 2015 |
| Grant date | May 2, 2017 |
| Priority date | — |
| Expiry date | Apr 16, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A wafer alignment apparatus includes a light source, a light detection device, and a rotation device configured to rotate a first wafer and a second wafer. The light source is configured to provide a first light directed to the first wafer and a second light directed to the second wafer. The light detection device is configured to detect reflected light intensity from the first wafer to find a position of at least one wafer alignment mark of the first wafer and to detect reflected light intensity from the second wafer to find a position of at least one wafer alignment mark of the second wafer.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.