Dependence of the Performance of Single Photon Avalanche Diodes on the Multiplication Region Width: Temperature and Field Effects

In this paper we report new theoretical results on the dependence of the performance of SAM SPADs on the width of the MR by comparing the effects of field-assisted dark carriers with temperature-assisted dark carriers as the width is varied. This sheds light on the characteristic difference in the performance between low-temperature operation and room-temperature operation. Furthermore, we introduce in our study the crucial role played by the location of the carriers within the different layers of the SPAD. We assume that photogenerated carriers are created in the absorber at random locations according to a uniform probability density; similarly, dark carriers are generated randomly in the MR and the absorber according to a uniform probability density in each layer. We consider SPADs with InP hole-injection MRs and InGaAs or InGaAsP absorbers. We use the recursive dead-space multiplication theory to calculate the generalized breakdown probability for all carriers generated in the SPAD according to a field-dependent spatial distribution of carriers (Hayat et al., 2003).