Modelling of ideal AlGaAs quantum well solar cells

Abstract

A theoretical model has been developed to determine the influence of the insertion of multi-quantum wells (MQW) over the conversion efficiencies of Al x Ga 1− x As solar cells. Open-circuit voltages, short-circuit current densities, J– V curves and conversion efficiencies have been calculated as functions of the well and barrier band gaps, width and depth of the wells, number of wells in the intrinsic region and the recombination rate in the interfaces. Particular emphasis is placed on the calculation of the photon absorption in Al x Ga 1− x As quantum wells. These results are matched with identical p-i-n solar cells without quantum wells. The outcomes of the model show that the insertion of MQW into the depletion region of a p-i(MQW)-n Al x Ga 1− x As solar cell can significantly enhance the conversion efficiencies. We demonstrated that for determined values of the studied parameters, the conversion efficiencies of the quantum well solar cell are higher than that of the corresponding cell without quantum wells.