Photodetector array having array of discrete electron repulsive elements

Photodetector arrays, image sensors, and other apparatus are disclosed. In one aspect, an apparatus may include a surface to receive light, a plurality of photosensitive regions disposed within a substrate, and a material coupled between the surface and the plurality of photosensitive regions. The material may receive the light. At least some of the light may free electrons in the material. The apparatus may also include a plurality of discrete electron repulsive elements. The discrete electron repulsive elements may be coupled between the surface and the material. Each of the discrete electron repulsive elements may correspond to a different photosensitive region. Each of the discrete electron repulsive elements may repel electrons in the material toward a corresponding photosensitive region. Other apparatus are also disclosed, as are methods of use, methods of fabrication, and systems incorporating such apparatus.