A novel full-chip afterpulsing evaluation technique for 116 × 160 Ge-on-Si SPAD array

This Letter presents a novel on-chip afterpulsing characterization method demonstrated using gated-mode short-wave infrared single photon avalanche diode arrays, effectively overcoming the measurement limitations of conventional methods. Through this approach, we first achieve a comprehensive evaluation of the full-chip afterpulsing effect by adjusting the ratio between gated-on time and gated-off time and employing a sampling window technique. Experimentally validated using a room-temperature-operated 160 × 116 Ge-on-Si single photon avalanche diode array, the approach clearly reveals the potential pixel-to-pixel variations in afterpulsing behavior across SWIR single-photon avalanche diode arrays, highlighting the critical importance of full-chip evaluation for designing and optimizing gating period.