Image sensors with backside trench structures
US9748298B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 30, 2015 |
| Grant date | Aug 29, 2017 |
| Priority date | — |
| Expiry date | Jul 13, 2035 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10F39/8063
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A backside illumination image sensor with an array of image sensor pixels is provided. Each pixel may include a photodiode, a storage diode, and associated circuitry formed in a front side of a semiconductor substrate. In accordance with an embodiment, a trench isolation structure may be formed directly over the storage diode but not over the photodiode from a back side of the substrate. The backside trench isolation structure may be filled with absorptive material and can optionally be biased to a ground or negative voltage level. A light shielding layer may also be formed over the backside trench isolation structure on the back side of the substrate. The light shielding layer may be formed from absorptive material or reflective material, and may also be biased to a ground or negative voltage level.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.