Patent attributes
A single photon avalanche diode may include a substrate and a plurality of junction structures supported by the substrate. The substrate may have an upper surface and a lower surface that are opposite to each other. The junction structures may support by the substrate to make contact with the upper surface of the substrate. The junction structures may include portions that overlap with each other in a vertical direction perpendicular to the substrate. Each of the junction structures may include a first impurity region having a first conductive type and disposed to make contact with the upper surface of the substrate, and a second impurity region having a second conductive type and disposed to make contact with the upper surface of the substrate and a bottom surface of the first impurity region. The first impurity region and the second impurity region in each of the junction structures may be configured to receive a bias voltage through the upper surface of the substrate.
