Backside illumination image sensors with reflective light guides
US8368157B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Apr 6, 2010 |
| Grant date | Feb 5, 2013 |
| Priority date | — |
| Expiry date | Apr 7, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10F39/8067
Abstract
Image sensors with backside illumination image pixel arrays are provided. An image pixel array may have image pixels that are formed on a silicon substrate having front and back surfaces. The pixel array may have photodiodes formed in the front surface. A dielectric stack may be formed on the front surface. The dielectric stack may include interconnect structures and reflective light guides. A color filter array may be formed on the back surface of the substrate. Microlenses may be formed on the color filter array from the side facing the back surface. The pixel array may receive incoming light through the microlenses. The incoming light may enter the substrate through the back surface. The incoming light may penetrate the substrate and may be reflected by a light reflector in the reflective light guide back towards the photodiode. The image pixel array may exhibit improved quantum efficiency, sensitivity, and image contrast.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.