Single-Event Transients in a PIN Photodiode and a Single-Photon Avalanche Diode Integrated in 0.35μm CMOS

Single-event transients (SETs) in a PIN photodiode and a single-photon avalanche diode (SPAD), both fabricated in the same 0.35μm CMOS process, are compared under heavy ion irradiation. The experimental results suggest that mainly the low-doped epitaxial layer defines the amount of collected charge. High current peaks at the output of the photodetectors, necessitate precautions in the quencher and read-out circuit design.