Design and Analysis of an Afterpulsing Auto-Correction System for Single Photon Avalanche Diodes

In this work, an auto-afterpulsing correction system for single photon avalanche photodiode (SPAD) is proposed and implemented which can be used in real-time to minimize the afterpulsing effect in SPAD. The system is based on passive quenching circuit and retriggerable monostable multivibrator and can be used for any SPADs with different bias voltages (Vb). Two different SPADs are used to evaluate the proposed system, one is a planar SPAD fabricated in-house (Vb is around 26V) and the other one is a commercial reach-through SPAD (Vb is around 126V). Experimental results show that for both SPADs, the afterpulsing probabilities can be effectively reduced to below 0.5% from 5% and 4% respectively. Results also show that, with a proper time interval threshold, the SPAD's afterpulsing probability can be maintained below 0.5% with the increasing of the bias voltage. The system developed is simple and can be used for effectively minimizing the afterpulsing effect for any SPADs that makes it very useful in low cost and compact SPAD based photon counting applications.