Simple Monte Carlo Simulator for modelling Linear Mode and Geiger Mode Avalanche Photodiodes in C++

Linear mode and Geiger mode Avalanche Photodiodes are widely used to detect weak optical signals, with the latter able to detect a single photon at a time. Practical simulators for these devices should accurately produce relevant device characteristics and not be overly computationally intensive. The Simple Monte Carlo Simulator, written in C++, offers such a combination and can simulate avalanche photodiodes made with Silicon, Gallium Arsenide and Indium Gallium Phosphide, with the potential to include other semiconductor materials. The software is available on The University of Sheffield Research Data Catalogue and Repository at https://doi.org/10.15131/shef.data.5683939 and on GitHub at https://github.com/jdpetticrew/Simple-Monte-Carlo-Simulator

Simulation of Al0.85Ga0.15As0.56Sb0.44 avalanche photodiodes

Al0.85Ga0.15As0.56Sb0.44 is a promising avalanche material for near infrared avalanche photodiodes (APDs) because they exhibit very low excess noise factors. However electric field dependence of ionization coefficients in this material have not been reported. We report a Simple Monte Carlo model for Al0.85Ga0.15As0.56Sb0.44, which was validated using reported experimental results of capacitance-voltage, avalanche multiplication and excess noise factors from five APDs. The model was used to produce effective ionization coefficients and threshold energies between 400–1200 kV.cm-1 at room temperature, which are suitable for use with less complex APD simulation models

Avalanche Breakdown Timing Statistics for Silicon Single Photon Avalanche Diodes

CCBY Silicon-based Single Photon Avalanche Diodes (SPADs) are widely used as single photon detectors of visible and near infrared photons. There has however been a lack of models accurately interpreting the physics of impact ionization (the mechanism behind avalanche breakdown) for these devices. In this work, we present a statistical simulation model for silicon SPADs that is capable of predicting breakdown probability, mean time to breakdown and timing jitter. Our model inherently incorporates carriers & #x0027; dead space due to phonon scattering and allows for non-uniform electric fields. Model validation included avalanche gain, excess noise factor, breakdown voltage, breakdown probability, and timing statistics. Simulating an n on-p and a p-on-n SPAD design using our model, we found that the n-on-p design offers significantly improved mean time to breakdown and timing jitter characteristics. For a breakdown probability of 0.5, mean time to breakdown and timing jitter from the n-on-p design were 3 and 4 times smaller compared to those from the p on n design. The data reported in this paper is available from the ORDA digital repository (DOI: 10.15131/shef.data.4823248)