Partially pinned photodiode for solid state image sensors

摘要

A pixelated image sensor having comprising a partially pinned photodiode which is formed a semiconductor of a first conductivity type formed on a surface of the sensor with at least one photodiode formed, within the semiconductor near the surface, the photodiode being formed from a second conductivity type opposite the first conductivity type; a pinning layer formed on the surface over at least a portion of the photodiode creating a pinned photodiode region, the pinning layer being formed from the first conductivity type; and an unpinned region formed near the surface in an area outside the portion used to form the pinning layer, the unpinned region is formed as a floating region that is employed as a capacitor. The partially pinned photodiode is useful in expanding the fill factor of photodetectors employing photodiode technology.