A device includes a single photon avalanche diode in a portion of a substrate, wherein the portion has an octagonal profile. The octagonal profile is delimited by a wall forming an octagonal contour around the portion. The device further includes an array of diodes, wherein each diode is located in a corner between four adjacent single photon avalanche diodes. Each single photon avalanche diode further includes a doped anode region. A shallow trench isolation is formed in each doped anode region. A polysilicon line forming a resistor is supported at the upper surface of the shallow trench isolation.