Wafer alignment mark scheme
US9863754B2 · kind B2 · utility
0Cited by
2References
21Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Sep 15, 2014 |
| Grant date | Jan 9, 2018 |
| Priority date | — |
| Expiry date | Sep 15, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2924/0002
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A wafer alignment apparatus includes a light source, a light detection device, and a rotation device configured to rotate a wafer. The light source is configured to provide light directed to the wafer. The light detection device is configured to detect reflected light intensity from the wafer to locate at least one wafer alignment mark of wafer alignment marks separated by a plurality of angles. At least two of those angles are equal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.