Lucky-drift model for impact ionization in amorphous semiconductors

A lucky-drift model for impact ionization has been recently successfully used to account for avalanche phenomenon in amorphous selenium (a-Se). We extend the calculations in order to compare the effect in a-Se with possible impact ionization phenomenon in another prototype amorphous semiconductor: hydrogenated amorphous silicon (a-Si:H). The results suggest that the higher phonon energy in a-Si:H as compared to a-Se shifts the threshold field …