RADIATION TOLERANCE OF AIInGaP AS A NEW TOP CELL FOR SUPER-HIGH EFFICIENCYMJ SPACE CELLS

摘要

30keV proton irradiation effects on AlInGaP solar cell as a new top cell for high efficiency III-V multi-junction (MJ) space solar cells are presented here for the first time. As the proton fluence increases over 1×1010cm-2, the Pmax and FF of the cell decrease rapidly, and the short-circuit current increases above the initial value interestingly, which is attributed to the broadening of depletion layer by the majority-carrier removal, at the fluence of 1×1010cm-2. From the changes in minority-carrier diffusion length (L) determined by the quantum efficiency modeling as a function of fluence, the damage constant KL for AlInGaP cell was estimated to be about 4.3×10-5. This value is lower than those observed in 3MeV proton irradiated InGaP, InGaAsP, and InGaAs cells. The maximum power recovery of the cell was observed by the minority-carrier injection enhanced annealing (1 A/cm2), and the annealing activation energy of 30keV proton irradiation-induced defects was determined as ΔE=0.42eV.