Afterpulsing Characteristics of Free-Running and Time-Gated Single-Photon Avalanche Diodes in 130-nm CMOS

The temperature-dependent afterpulsing characteristics of single-photon avalanche diodes (SPADs) fabricated in a standard digital 130-nm CMOS technology are described. Avalanche interarrival time statistics are analyzed to obtain the afterpulsing probabilities (APs) for 81- and 110- $\mu \text{m}^{2}$ active area SPAD pixels using free running (FR) and time-gated (TG) front-end circuits. A strong reduction in AP was evident in the TG mode compared with the FR SPAD pixels. Optimal operating conditions in terms of hold-off time and temperature were found for <1% AP.