Effect of field dependent mobility on the analytical modeling of emitter saturation current of a silicon solar cell

In this paper an analytical model of emitter saturation current of a silicon solar cell has been developed to show the effects of field dependent carrier mobility and of both doping dependent SRH and Auger recombination mechanisms in a non-uniformly doped emitter. In developing this model the doping dependency of carrier lifetime as well as the bandgap narrowing effect due to heavy emitter doping level is considered. An exponential approximation technique is used to deduce an analytically solvable governing differential equation. The developed model shows that the emitter saturation current has significantly varied due to the field-dependency of carrier mobility for thin emitter as well as simultaneous consideration of both SRH and Auger recombination for wide emitter.