Global shutter image sensors with light guide and light shield structures
US10325947B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 16, 2014 |
| Grant date | Jun 18, 2019 |
| Priority date | — |
| Expiry date | Mar 5, 2036 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10F39/803
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An image sensor operable in global shutter mode may include an array of image pixels. Each image pixel may include a photodiode for detecting incoming light and a separate storage diode for temporarily storing charge. To maximize the efficiency of the image pixel array, image pixels may include light guide structures and light shield structures. The light guide structures may be used to funnel light away from the storage node and into the photodiode, while the light shield structures may be formed over storage nodes to block light from entering the storage nodes. The light guide structures may fill cone-shaped cavities in a dielectric layer, or the light guide structures may form sidewalls having a ring-shaped horizontal cross section. Metal interconnect structures in the dielectric layer may be arranged in concentric annular structures to form a near-field diffractive element that funnels light towards the appropriate photodiode.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.