Image sensor for mitigating dark current

摘要

One or more embodiments of techniques or systems for mitigating dark current of an image sensor are provided herein. Generally, a silicon interface, such as an edge of a dielectric region or an edge between a back side interface (BSI) region and a pass region, is a source of electrons or holes which cause dark current. In some embodiments, the image sensor includes a surface protect region. For example, the surface protect region is doped with a first doping type and a photo-diode of the image sensor is doped with the same first doping type. In this manner, the surface protect region acts as an electron magnet or a hole magnet for electrons or holes from the silicon interface, thus mitigating electrons or holes from the silicon interface from being collected by the photo-diode, for example.

主权项

1. An image sensor for mitigating dark current, comprising:
a first region comprising a first doping type; a second region comprising a second doping type, the second doping type opposite of the first doping type, the first region surrounded by the second region; a first surface protect region above the second region and comprising the first doping type; a first silicon interface comprising an edge between the first surface protect region and a dielectric region above the first surface protect region; a second surface protect region below the second region and comprising the first doping type; and a second silicon interface comprising an edge between a back side interface (BSI) region and a pass region below the second surface protect region.