Image sensors with reflective optical cavity pixels
US9373732B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Jan 21, 2013 |
| Grant date | Jun 21, 2016 |
| Priority date | — |
| Expiry date | Dec 24, 2033 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10F39/806
Abstract
An image sensor may be provided having a pixel array that includes optical cavity image pixels. An optical cavity image pixel may include a photosensitive element in a substrate and a reflective cavity formed from a frontside reflector that is embedded in an intermetal dielectric stack, a backside reflector formed in a dielectric layer above the photosensor that partially covers the photosensor, and sidewall reflectors formed in the substrate between adjacent photosensors using deep trench isolation techniques. Each optical cavity image pixel may also include a light-guide trench above the photosensor that guides light into the reflective cavity for that pixel. Each optical cavity pixel may also include color filter material in the trench. Light that is guided into the reflective cavity by the light-guide trench may experience multiple reflections from the reflectors of the reflective cavity before being absorbed and detected by the photosensor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.