Modelling the effect of 1 MeV electron irradiation on the performance degradation of a single junction Al<inf>x</inf>Ga<inf>1&#x2212;x</inf>As/GaAs solar cell

Abstract

We have modelled the effect of 1 Me V electron irradiation on the performance degradation of a single junction AI,Gal_xAsIGaAs solar cell. The irradiation-induced defects result in energy states within the energy gap of the semiconductors. In this paper. we first model the effect of 1 MeV electron irradiation for the electron fluences from 1 x 10 14 to 1 xl0 16 elem2 using the'parameters of the irradiation-induced defects on the performance degradation of a solar cell. Then we present the results of a study for the effect of the layer thickness on the performance degradation of the solar cell. We will show that by choosing appropriate thickness for the layers, it is possible to considerably reduce the performance degradation of the solar cell.

Effect of electron irradiation fluence on the output parameters of GaAs solar cell

“…Simulation results show good correlation with other simulated results [13,14] with an agreement inferior to 15% except for the efficiency of the 2D model of reference [14] for which the difference is of 22%. This can be explained by the solar cell structure and the dimensions of the models which are in the same order of magnitude but with certain differences.…”

“…Results are in good agreement with other numerical results validated with good matching to experimental measurements in Refs. [13,14]. The differences are inferior to 5% for most values for the 2D models.…”

“…The extracted J sc , V co , FF and h before irradiation are 28.58 mA/cm 2 , 0.974 V, 0.887 and 18.30% respectively. In order to confirm the reliability of our model, in Table 4 we have compared the output parameters of the solar cell, before irradiation, with experimental and numerical data [13,14,23].…”

“…On the other hand, 10 16 cm À2 electron irradiation fluence creates three electron traps and four holes, whose concentrations vary between 10 13 and 10 15 cm À3 . Electrical output parameters of the J(V) characteristics obtained by simulation for the different electron fluences are extracted and confronted to 1D and 2D simulation results [13,14]. Simulated output parameters are shown in Table 5.…”

“…Recombination centers close to the intrinsic Fermi level have been pointed to engender the decrease of performance of GaAs solar cells as they induce a decrease of the lifetime of the minority carriers [9,10]. This can be appreciated in a model by decoupling the defects and simulating the single effect of each defect [14].…”