The invention discloses a high-performance single-
photon pixel spad structure, and relates to the technical field of integrated circuits. The device comprises a
silicon surface, a
cathode and an
anode,
high voltage is applied to the
cathode, and the
anode is grounded; impurities with different properties are doped on the surface of
silicon for multiple times, ions of N-type impurities and P-type impurities are injected with energy to form a plurality of back-to-back PN junctions, and finally the plurality of back-to-back PN junctions are connected in parallel; multiple times of
doping are adopted, so that signals can be effectively led out from the deep part, and any two PN junctions are connected in parallel, so that the depth of a space
depletion region is effectively increased in the longitudinal direction; the
cathode and the deep N well injection are isolated from the P-type impurities by using epitaxial layer low-concentration
doping; and the
anode and the deep P well injection are isolated from the N-type impurities by using epitaxial layer low-concentration
doping. According to the invention, the depth of the
depletion region is effectively expanded, the detection efficiency is improved, and the
diffusion time of photoelectrons is reduced, so that the time
jitter is reduced, and the SPAD avalanche
voltage can be effectively reduced.