BSI chip with backside alignment mark
US12094997B2 · kind B2 · utility
0Cited by
6References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 25, 2022 |
| Grant date | Sep 17, 2024 |
| Priority date | — |
| Expiry date | Jul 25, 2042 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L2223/54426
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method includes forming image sensors in a semiconductor substrate. A first alignment mark is formed close to a front side of the semiconductor substrate. The method further includes performing a backside polishing process to thin the semiconductor substrate, forming a second alignment mark on the backside of the semiconductor substrate, and forming a feature on the backside of the semiconductor substrate. The feature is formed using the second alignment mark for alignment.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.