Germanium-silicon light sensing apparatus

An image sensor array comprising:

• a carrier substrate;
• a first group of photodiodes coupled to the carrier substrate, wherein the first group of photodiodes comprise a first photodiode, and wherein the first photodiode comprises:
• a semiconductor layer configured to absorb photons at visible wavelengths and to generate photo-carriers from the absorbed photons;
• a first carrier-collection region configured to collect a portion of the photo-carriers generated by the semiconductor layer;
• a first readout region coupled to a first readout circuitry, the first readout region configured to provide the photo-carriers collected by the first carrier-collection region to the first readout circuitry;
• and
• a first gate coupled to a first control signal that controls a carrier transport between the first carrier-collection region and the first readout region;
• and
• a second group of photodiodes coupled to the carrier substrate, wherein the second group of photodiodes comprise a second photodiode, and wherein the second photodiode comprises:
• a germanium-silicon region fabricated on the semiconductor layer, the germanium-silicon region configured to absorb photons at infrared or near-infrared wavelengths and to generate photo-carriers from the absorbed photons;
• a second carrier-collection region configured to collect a portion of the photo-carriers generated by the germanium-silicon region;
• a second readout region coupled to a second readout circuitry, the second readout region configured to provide the photo-carriers collected by the second carrier-collection region to the second readout circuitry;
• a second gate coupled to a second control signal that controls a carrier transport between the second carrier-collection region and the second readout region;
• a third readout region coupled to a third readout circuitry, the third readout region configured to provide the photo-carriers collected by the second carrier-collection region to the third readout circuitry;
• and
• a third gate coupled to a third control signal that controls a carrier transport between the second carrier-collection region and the third readout region.