Decoupling the dark count rate contributions in Ge-on-Si single photon avalanche diodes

Single Photon Avalanche Diodes (SPADs) are semiconductor devices capable of accurately timing the arrival of single photons of light. Previously, we have demonstrated a pseudo-planar Ge-on-Si SPAD that operates in the short-wave infrared, which can be compatible with Si foundry processing. Here, we investigate the pseudo-planar design with simulation and experiment to establish the spatial contributions to the dark-count rate, which will ultimately facilitate optimisation towards operation at temperatures compatible with Peltier cooler technologies.