Modelling superlattice avalanche photodiodes: combining discrete ionisation model with experimental data

A discrete ionisation model for the gain, excess noise factor and quantum efficiency for a specific superlattice APD has been developed taking into account the material properties of the device. Preliminary validation of the model has been effected against experimental measurements reported by Capasso et al. (Appl. Phys. Lett., vol.40, no.1, p.38-40, 1982). A mathematical model of the device is produced describing the photogeneration of carriers due to distributed absorption in the superlattice layers. By combining this with the parameters of the discrete ionisation model, derived from practical measurements, performance assessment is effected