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A self-consistent numerical Poisson-Schrödingerdrift-diffusion solver is described for simulation of multiple-quantum-well (MQW) Al[sub x]Ga[sub 1-x]As-GaAs solar cells. The rates of escape, capture, and recombination of photoexcited carriers in quantum wells embedded in the intrinsic region of a p-i-n device are self-consistently incorporated in the model. The performance of the device for various quantum-well configurations is investigated and the device characteristics are related to the dynamics of capture, escape, absorption, and recombination of carriers in the quantum wells. Our results show that the incorporation of MQWs in the intrinsic region of a p-i-n solar cell can improve the conversion efficiency of non-optimal devices, if the device is designed based on careful consideration of the behavior of the photoexcited carriers in the quantum wells. Specifically, we found out that an Al[sub 0.1]Ga[sub 0.9]As-GaAs cell with multiple quantum wells of 150 Å is more efficient than an identical single bandgap Al[sub 0.1] Ga[sub 0.9]As cell with no quantum wells, but less efficient than a single bandgap GaAs cell without such quantum wells. [ABSTRACT FROM AUTHOR]

Abstract: A self-consistent model for escape and capture of carriers in quantum wells is described. The model accounts for carrier dynamics in the quantum wells by calculating the rates of escape and capture of photo-excited carriers in the wells, and including these rates in a self-consistent solution of the Poisson, Schrödinger, and drift–diffusion equations. The results obtained are in good agreement with those experimentally measured or theoretically calculated by others. Furthermore, the escape and capture rates calculated are in compliance with the requirements of detailed balance theory. [Copyright &y& Elsevier]