Modeling Tunneling-assisted Generation-recombination Rate in Space-charge Region of Pn A-si:h Junction

A theoretical model of generation-recombination mechanism of charge carriers in pn a-Si:H junctions with high internal builtin electric fields is developed in which the capture-emission transitions are treated in a similar way as in the SRH generationrecombination approach. In this way, the effects of the tunneling-assisted transitions between the transport edges and the traps are expressed by an enhanced capture cross-section which in turn increases the generation-recombination rate of charge carriers. The tunneling and thermal capture and emission of carriers to and from localized states determine the occupancy function in the mobility gap of a-Si:H. Generation-recombination dynamics are then expressed by virtue of occupancy function and the continuous distribution of states in the gap of a-Si:H.