High Efficiency AlxGa١-xAs/GaAs Quantum Wells Solar Cells

An analytical expression for the maximum obtainable photoconversion efficiency of graded band gap AlxGa1-xAs/GaAs quantum wells solar cell was presented. Computer program WELL was designed to simulate the photocurrent density, spectral response and conversion efficiency to the proposed model. To improve this model, the effect of the number wells was studied. The photovoltaic parameters obtained from this model with 50 quantum wells are Jsc =55 mA/cm2, Voc= .924 V, FF= .875 and = 52.8 % under AM1.5D solar spectrum conditions. Significant enhancements in short-circuit current and conversion efficiency have been obtained.