Effects of multiplication layers on dark current components of InGaAs/InP avalanche photodiodes

Based on results from the Silvaco Atlas device simulation software, a separate absorption grading charge multiplication InGaAs/InP avalanche photodiode has been modeled. The Shockley–Read–Hall current, avalanche amplification current, trap-assisted tunneling current, and band-to-band direct tunneling current are combined and considered as the dark current. Individual components of the dark current have been obtained separately through numerical simulation. Due to the multiplication effect, the influence of the multiplication layer on the dark current components has been studied. The simulation results are analyzed based on semiconductor physics knowledge. The conclusions presented provide some theoretical guidance for the optimum design of avalanche photodiodes.