Analytical Modeling of the Base Dark Saturation Current of Drift-Field Solar Cells Considering Auger Recombination

Abstract

In this work, an analytical model has been developed for the dark saturation current in the heavily-doped base region of a drift-field Si-solar cell. Unlike the conventional models available in the literature, this model incorporates both the SRH (Shockley-Read-Hall) and the Auger recombination. The mathematical intractability due to this consideration has been resolved by using an elegant exponential approximation technique. The simulations carried out by the developed model shows that the Auger recombination becomes significant even for a 1 µm wide base when surface recombination velocity is lowered to the order of  10^4 cm/sec  and/or when the doping level is of the order of 10^19 cm-3 .

Keywords

• - Drift-Field Solar Cell, Dark Saturation Current, SRH Recombination, Auger Recombination, Non-uniformly Doped Base

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