Monte Carlo simulation of impact ionization in photodetectors
Impact ionization in optical detectors has been studied using a self-consistent Monte Carlo method. Current multiplication was found to be sensitive to both the applied potential and the incident light intensity. The amount of current multiplication was significantly higher than might be expected under the assumption that the field in the device is unchanged by the photogenerated carrier distribution. The potential within the device was also found to be significantly affected by the impact-ionization process and this in turn gave rise to interesting oscillations in the current at higher incident light intensities and potentials.